Introduction

A phone call, and shortly afterwards one sits waiting, under the guidance of a shaman or psychologist, for the overwhelming effects of the hallucinogen ayahuasca. In the Netherlands this has been possible for a few years. People who want to take ayahuasca independently can purchase the ingredients in some smart shops and souvenir shops. In the final decade of the old millennium, interest in this remarkable plant brew grew considerably. So too did the number of people, including many scientists, who had experienced the effects of ayahuasca. As a result, information about ayahuasca increased sharply, particularly in recent years. Several books on the subject have recently been published, and there are now tens of megabytes of internet pages describing different aspects of ayahuasca use. For those interested, it is also possible to use ayahuasca on an organised journey with "real" shamans in an authentic environment in South America.

This is where ayahuasca has its origin, in the largest and most diverse rainforest on earth. The traditional use of ayahuasca has a long history here that goes back several thousand years (Naranjo, 1986). Therapeutic applications have always played an important role. The term ayahuasca comes from the Quechua language, spoken by millions of inhabitants of the Andean highlands of Peru, Bolivia, and Ecuador in various dialects, and means roughly "vine of the soul" or "vine of death." The word can refer to the base ingredient, the plant Banisteriopsis caapi, to the brew that is often prepared with the addition of other plants, and also to the spirit that animates the plants. The term is used primarily in the Bolivian, Peruvian, and Ecuadorian parts of the Amazon basin. The most well-known synonyms for ayahuasca in traditional use are caapi and hoasca in Brazil (the transliteration of ayahuasca into Portuguese), and yage or yaje in the Ecuadorian and Bolivian Andes. Other names include natema among the Jivaro in Ecuador, nishi among the Shipibo-Conibo in Peru, and biaxi among the Sibundoy in Colombia (Harner, 1972; Ilius, 1987; Bristol, 1966).

In the West, ayahuasca became known about 150 years ago through the descriptions of Richard Spruce (1817-1893), who between 1849 and 1864 collected plants in various countries around the Amazon and made extensive botanical notes. Other expeditions followed, mapping the use of ayahuasca. Over 130 years later, 72 traditional groups in South America are known to use ayahuasca and have 42 different names for it (Luna, 1986). In the same countries, ayahuasca is now also used in cities by curanderos (healers) within a therapeutic context. In addition, churches emerged in Brazil during the last century in which ayahuasca is revered as the most important sacrament. In 1996 the Brazilian government was aware of 22 sects that officially used ayahuasca (Dobkin de Rios, 1996). The best known are the Santo Daime and the Uniao do Vegetal. The expansion of these churches has especially led to ayahuasca now being used on a larger scale outside South America.

In the Netherlands, ayahuasca rituals have been organised for years by church communities but also by individuals. The situation changed in autumn 1999, after it had been possible for several years to participate more or less officially in various ayahuasca rituals. During a ritual of the Santo Daime church in Amsterdam, police conducted a raid and the rituals were banned on the grounds of the illegal status of DMT, one of the active constituents. Adherents of the French Santo Daime church were also harassed and some were even imprisoned for several weeks. The law on religious freedom now stood in conflict with drug legislation. In addition, these developments hampered important research into ayahuasca as a therapeutic agent. There are in fact many indications that ayahuasca, when used in the right context, has the ability to heal a range of conditions. Its supposed effectiveness in breaking drug addiction makes it particularly interesting. Effective therapies for certain addictions, such as cocaine, are lacking in healthcare. In South America, ayahuasca has been applied with success in this context for years. Nevertheless, the relevant scientific research into ayahuasca was getting underway only slowly.

Other hallucinogenic substances had already been applied in the treatment of alcohol and other drug addictions in the 1950s and 1960s. A large number of research reports describe enormously high success rates in the treatment of addictions, but also a number of other conditions. After most of the available hallucinogens were placed on Schedule I of the Opium Law at the end of the 1960s and early 1970s without further study, these substances almost disappeared from the scientific stage. Fearful emphasis was placed on the dangers of hallucinogens to public health, dangers exaggerated and distorted by the media. Only at the end of the last millennium did the number of publications on hallucinogens, now also known under the less pejorative term entheogens, begin to rise again.

Today, scientists from various backgrounds in different countries are working to map different facets of entheogens objectively and often with a multidisciplinary approach. Enormous successes are again being reported by therapists. To this day, however, no generally accepted statements about the therapeutic value of hallucinogens have been made. While controlled clinical studies of ayahuasca are lacking, there is nonetheless much to be found in the literature that could contribute to the development of a treatment programme. Because ayahuasca has attracted interest in a number of different scientific disciplines, the information in the literature is enormously broad. In contrast to most Western medicines, for an effective application of ayahuasca not only the pharmacological properties but especially personal and environmental factors are of importance.

The purpose of this literature thesis is to set out the information from different fields, in particular botany, anthropology, pharmacology, psychiatry, and psychology. From a multidisciplinary perspective, different facets of the ayahuasca phenomenon are described and their relevance for possible therapeutic application in modern healthcare and addiction care is explained.

¹ Many Western doctors and psychologists are convinced that entheogens can provide access to spiritual dimensions of consciousness and even to mystical experiences indistinguishable from classical religious mysticism. The term entheogen refers to a direct experience of the divine (derived from Greek: entheos means "god within, or the divine within," and gen indicates "becoming") and was coined in 1970 by R. Gordon Wasson, Jonathan Ott, and others to replace the negatively charged terms such as hallucinogen (hallucination-causing), psychodysleptic (mind-disrupting), and a range of other misleading terms.

Chapter 1: The Plants and the Substances

Banisteriopsis caapi

a. Botany

Setting aside some superficial reports of a "devil's drink," Richard Spruce (1817-1893) was the first to write about the entheogen ayahuasca during his multi-year stay in the Amazon, about 150 years ago. He saw the Tukano Indians of the Rio Vaupes in Brazil using a plant-based, entheogenic drink during their rituals. He examined the plant material and discovered a previously unidentified species. He gave this new plant from the Malpighiaceae family the name Banisteria caapi (Schultes, 1968). In the same period, he observed ayahuasca use among the Guahibo Indians of the upper Orinoco in Colombia and Venezuela, and among the Ziparo Indians of the Peruvian Andes. He described the preparation of Banisteria caapi into ayahuasca and the effects that ayahuasca had on him personally. He collected some specimens of a flowering Banisteria caapi and sent them for chemical analysis to Kew Gardens in England (Reichel-Dolmatoff, 1975; Schultes, 1968), where a description of his discovery appeared shortly afterwards. His detailed notes were not published until more than fifty years later (Spruce, 1908). While Spruce recognised the psychoactivity of Banisteriopsis caapi, as the plant is now called, he attributed the effects of ayahuasca primarily to the additives. Later it became clear that he was right.

A wider audience was reached by the notes of the Ecuadorian geographer Manuel Villavicencio, made a few years after Spruce among three tribes near the Rio Napo. He was the first outsider to publish his experiences with ayahuasca (Villavicencio, 1858). In 1923 a film about yage ceremonies was shown at the annual meeting of the American Pharmaceutical Association. Other early accounts came from Rusby and White on the use of yage in Bolivia, and from Varnoff and Jezepezuk from Colombia (Stafford, 1992). Interest grew, more expeditions followed, and ayahuasca proved to be a pan-Amazonian drink (Schultes and Hofmann, 1980). The plant Banisteriopsis caapi grows wild in the areas of the Orinoco and Amazon basins, encompassing Venezuela, Colombia, Ecuador, Peru, Bolivia, and Brazil. It also grows on the other side of the Andes in Ecuador (Naranjo, 1979).

Banisteriopsis caapi is not, however, the only plant used by indigenous peoples as the base ingredient for ayahuasca. In 1986 a strict selection of valid ayahuasca species (and some synonyms from the literature) was published:

• Banisteriopsis caapi (B. inebrians, B. quitensis)
• Banisteriopsis muricata (B. argentea, B. metallicolor)
• Callaeum antifibrile (Cabiparaensis, Mascagnia psilophylla)
• Tetraptyrus styloptera (T. methystica) (Gates, 1986b)

According to a more liberal analysis of the literature, Jonathan Ott adds several additional species: Banisteriopsis longialata, Banisteriopsis lutea, Banisteriopsis martiniana var. subenervia, Lophantera lactescens, and Tetrapterys mucronata (Ott, 1994).

The scientific search for these plants took several decades. Researchers used different scientific names for the same plants, sometimes mistakenly believing they had encountered a never-before-identified plant. Different species of the same family can look very similar to an untrained eye, and many of the early ethnographic descriptions with regard to botany are not very detailed. Further confusion arose not only because different traditional groups name the plants for ayahuasca in different languages or dialects, but also because ayahuasceros use a different and more extensive classification system for the plants than Western botanists. Different specimens of Banisteriopsis caapi are considered different plants by an ayahuascero, on the basis not only of location, age, and growing conditions, but also on other factors perhaps less or not at all accessible to a scientific approach.

b. The Harmala Alkaloids

The effects of Banisteriopsis caapi are primarily the result of an interaction between three substances: harmaline, harmine, and d-1,2,3,4-tetrahydroharmine (Hochstein and Paradies, 1957). As with the identification of the ayahuasca plants, the identification of the active constituents was characterised by prolonged confusion. The first name for an extract from ayahuasca was given by the Colombian pharmacist R. Zerda Bayon in 1905. He called the extract Telepatina (Deulofeu, 1967). Fischer Cardenas, who first performed successful chemical work with crystalline alkaloids from Banisteriopsis, used the name telepathine for the substance he isolated (Fischer Cardenas, 1923). In 1925, Barriga Villalba isolated yayeina. Fischer Cardenas and Villalba did not know they were dealing with Banisteriopsis species (Ott, 1993). Two years later, telepathine was isolated in its pure form from authentic Banisteriopsis caapi (Perrot and Raymond-Hamet, 1927a, 1927b). Around that time, Louis Lewin in Germany isolated banisterine from Banisteria caapi (Lewin, 1928, 1929). Elger demonstrated in 1928 that the substance he had isolated from South American vines was identical to synthetic harmine and harmine from Peganum harmala (Elger, 1928). It took more than ten further years before it was clearly demonstrated that Telepatina, Yaydine, and Banisterine were synonyms for harmine (Chen and Chen, 1939). The results of Paradies and Hochstein mentioned above were confirmed by other researchers. It was later shown that Banisteriopsis caapi, in addition to harmine, harmaline, and tetrahydroharmine, also contains many other alkaloid constituents (Rivier and Lindgren, 1972; Hashimoto and Kawanishi, 1975).

c. Pharmacology of the Harmala Alkaloids

The three molecules harmaline, harmine, and d-1,2,3,4-tetrahydroharmine belong to the group of beta-carbolines, which occur fairly widely in the plant kingdom. These beta-carbolines have an inhibitory effect on the enzyme monoamine oxidase (MAO). MAO is involved in the breakdown of important neurotransmitters in the brain, including dopamine and serotonin. MAO is temporarily inhibited in its action by the beta-carbolines, which leads among other things to elevated serotonin levels in the brain. The MAO-inhibiting effect was first clearly described in 1958 (Udenfried et al., 1958).

Particularly the beta-carbolines harmine and tetrahydroharmine contribute to the MAO-inhibiting effect of Banisteriopsis species. Harmaline has a comparable and even stronger effect than harmine but is present at much lower concentrations. These ayahuasca alkaloids share this property with both other natural and synthetic beta-carbolines (McIsaac and Estevez, 1966). The third alkaloid tetrahydroharmine (THH) simultaneously contributes in its own way to an increase in the amount of serotonin in the brain available for neural transmission. THH inhibits the reuptake of serotonin into the presynaptic neuron (Airaksinen, 1980). This effect of THH is, however, much smaller than that of the SSRIs widely used in depression, including Prozac, which in interaction with MAO inhibitors could produce dangerous serotonin concentrations (Sternbach, 1991; Neuvonen et al., 1993). This is the greatest danger associated with the MAO inhibitors in ayahuasca. In general, people taking serotonergic medication would be better advised not to use ayahuasca (Callaway, 1993, 1994a; Callaway and Grob, 1998). It is also important to follow a certain diet before taking ayahuasca. Tyramine is an amino acid that is normally broken down by MAO. Through the action of the MAO inhibitors, high concentrations of tyramine can accumulate in the body, which can lead to a strong rise in blood pressure and heart rate, accompanied by severe headache and, in extreme cases, death. Foods with a high tyramine content should be avoided before taking ayahuasca. Certain medications and other drugs should also not be combined with ayahuasca.

There are contradictory results regarding other aspects of the action of the harmala alkaloids. While most older studies noted a stimulating effect on the central nervous system (Lewin, 1928; Gunn, 1937; Halpern, 1930a and b), Claudio Naranjo concluded after extensive research into the human pharmacology of the ayahuasca alkaloids that the results are difficult to interpret, but that the central action resembles more that of a sedative than a stimulant (Naranjo, 1967). His findings are supported by the fact that passionflower with the same alkaloids is used as a tranquilliser in traditional medicine. These alkaloids can, by themselves, also produce various entheogenic effects when administered by injection, in contrast to the oral route where up to almost one gram of alkaloids failed to produce these effects (Pennes and Hoch, 1957). Naranjo, however, also found hallucinogenic effects with oral administration of a much lower dose of harmaline (Naranjo, 1967). The bitter taste, nausea, and vomiting following ingestion of ayahuasca preparations are also attributed to the beta-carbolines.

Ayahuasca Additives

a. Botany

The use of ayahuasca based exclusively on Banisteriopsis species is more the exception than the rule. In general, during the preparation process, other plants are added that contain psychoactive substances and largely determine the entheogenic and medicinal effects. It may be assumed that every shaman has their own ayahuasca recipes and keeps certain additions and preparation methods secret. Research into the medicinal practice among the Siona Indians of Putumayo (Colombia), who are known for their extensive knowledge of plants, revealed that this group distinguishes 17 classes of yage, each producing a characteristic visionary state (Schultes, 1968; Reichel-Dolmatoff, 1970; Schultes, 1972). Even more strongly differentiated classifications of the ayahuasca additives can be found in the literature. According to J. Ott, all these additions can be divided into three classes:

1. Non-psychoactive therapeutic additives that are used on the basis of their pharmacological properties or mythical significance for the treatment of specific somatic complaints. Research shows that four of the five most commonly used plant medicines against rheumatism in the Amazon are also used as ayahuasca additives (Prance and Kallunki, 1984).

2. Stimulating additives are added to ayahuasca to provide extra energy for the work with ayahuasca. For this purpose, among others, Ilex guayusa (caffeine) and Guarana but also cocaine-containing plants are added (Ott, 1995).

3. Visionary, or entheogenic, ayahuasca additives receive the most attention in the literature. These plants are used to intensify the ayahuasca visions or to evoke specific aspects of the entheogenic experience. Ott divides the plants in this category into four subgroups.

3a) Nicotiana species (Nicotine). Used in the right context, tobacco in South America is seen as a powerful medicine and not a health hazard. Tobacco is not only used on a large scale in the Amazon region but is deeply interwoven in pan-American shamanism and is even seen by some Indians as a greater teacher than ayahuasca (Wilbert, 1987). From early pre-Columbian times to the present, tobacco has been an important medium for magical-religious, medicinal, and recreational purposes (Wilbert, 1991). These are the potent leaves of Mapacho, Nicotiana rustica or Nicotiana tabacum, from the Solanaceae family. In ritual contexts, tobacco is not only inhaled but also drunk as a decoction from plant material (Harner, 1972).

3b) Brugmansia species (Tropane alkaloids). These plants, which contain strong psychoactive substances, are also used separately by shamans alongside incorporation into ayahuasca, for instance among the Shipibo-Conibo shamans. Due to an increased risk of permanent psychopathological conditions or even death, these plants are generally used only rarely. Among the Shipibo-Conibo, these plants are associated with black magic (Ilius, 1987).

3c) Brunfelsia species (Scopoletin). These species are also used by Indians both on their own and as an additive to ayahuasca (Schultes and Hofmann, 1980).

d. Chacruna and Chagropanga (DMT)

Chacruna is the Quechua word for a plant referred to in the botanical literature as Psychotria viridis. It also encompasses P. carthaginensis, P. horizontalis, P. marginata, P. stenostachya, P. alba, and other species from the Rubiaceae (coffee) family. Chagropanga refers to the species Diplopterys cabrerana (= Banisteriopsis rusbyana). Both Chacruna and Chagropanga contain the short-acting entheogen DMT (dimethyltryptamine) and related substances, and are added to ayahuasca to intensify the visions (Ott, 1995). Psychotria viridis and Diplopterys cabrerana are the classic and most widely used ayahuasca additives in traditional contexts. Especially the active constituents from these plants are largely responsible for the effects of ayahuasca. These plants, or rather their active constituents DMT and related tryptamines, produce no effect by themselves via the oral route. DMT is broken down by monoamine oxidase, as are several neurotransmitters in the brain. As described below, MAO is temporarily inhibited by the beta-carbolines in ayahuasca, allowing DMT the possibility of remaining active in the body. How the Indians discovered that the different plants need to be taken in combination to produce the actual entheogenic experience is not clear.

b. DiMethylTryptamine

DMT is thus the strongest entheogenic component of ayahuasca in the form of Chacruna and Chagropanga. It is referred to in the literature as N,N-dimethyltryptamine, Nigerine, desoxybufotenine, and 3-(2-dimethylaminoethyl)-indole, and is a prototype among the indole alkylamines. It was first synthesised in 1931 by Manske (Manske, 1931) and independently isolated from Mimosa hostilis in 1946 by Goncalves de Lima, and from Piptadenia peregrina in 1955 by Fish, Johnson, and Horning (Fish, Johnson and Horning, 1955). In the same period, the entheogenic effects of DMT were first recognised and investigated, and the substance was subsequently isolated from a number of different plants, including Acacia, Anadenanthera, Mimosa, Piptadenia, and Virola species. The first descriptions of the extreme but brief entheogenic effects of pure DMT were published by the Hungarian psychiatrist and pharmacologist Stephen Szara, who conducted clinical work and experiments. He also discovered the oral inactivity of DMT, though the mechanisms of enzymatic breakdown were not yet known. The synergistic interaction between the MAO-inhibiting beta-carbolines and the psychoactive DMT was first clearly described in 1958 (Udenfried et al., 1958). That DMT is actually responsible for the greater part of the effects of ayahuasca, and that it becomes orally active through the beta-carbolines, was not experimentally confirmed until 1984 (McKenna et al., 1984).

c. Pharmacology of DMT

DMT is a particularly interesting substance for several reasons. First, DMT has been demonstrated in healthy, normal brains (Callaway, 1995a). What function endogenous DMT has in the everyday functioning of the brain is unclear, but it has been suggested that it could play a role in the production of visions during REM sleep (Callaway, 1988). Second, DMT has affinity with certain subgroups of serotonin receptors in the brain, through which it could have a modulatory effect on the flow of information (Callaway and McKenna, 1998). The action of DMT on certain systems in the brain can possibly explain part of the therapeutic effects of ayahuasca. DMT via ayahuasca is a 5HT-1a agonist, a 5HT-2 antagonist, and has a partially agonistic effect on 5HT-2 receptors (Deliganis et al., 1991). These agonists and antagonists of serotonin (5HT) had already been linked earlier to a reduction in craving. A deficiency of serotonin is also associated with mental disorders such as violent alcoholism, depression, anxiety, and suicide. The healing action of ayahuasca for these conditions, claimed by various ayahuasca therapists, could thereby be partly explained.

An effect on the serotonergic system in the brain also emerges from a study among members of the Uniao do Vegetal. People who had regularly drunk ayahuasca over several years showed on average a 25% higher density (Bmax) of 5HT receptors compared with the control group and literature values. The same individuals proved to be more stable and better integrated than those in the control group, and showed no depression or other psychological problems (Callaway et al., 1994). The effects that ayahuasca has on the serotonin system have important implications for understanding depression. Elevated serotonergic activity is precisely what antidepressants are meant to achieve. Further research in this area could lead to a new and effective treatment for depression (Callaway, 1994). Research into the pharmacological aspects of DMT and ayahuasca with regard to addiction, depression, and other pathological conditions is, however, strongly limited. The greater part of the relevant research still needs to be carried out.

Ayahuasca Analogues and Pharmahuasca

The remarkable effects of ayahuasca are thus based on the combination of beta-carbolines with MAO-inhibiting action and dimethyltryptamine and related tryptamines. In South America, a large number of these combinations with indigenous plants are possible. But it proves to be an almost universal possibility, since the relevant substances are found almost everywhere in the plant kingdom. Theoretically, therefore, thousands of plant combinations are possible that can bring about the basic principle of ayahuasca. Combinations that are not traditionally used are referred to as ayahuasca analogues. The chemist Jonathan Ott devoted an entire booklet to this subject (Ott, 1994). The most commonly used beta-carboline source outside South America is in all likelihood the seeds of Peganum harmala, the plant from the Zygophyllaceae family from which harmine was first isolated, which also contains harmaline and tetrahydroharmine, though in different proportions. Originally from Asia, where it is known as medicine and aphrodisiac, it is primarily used for dyeing textiles and as a kind of incense in fire. Whether this plant was also taken in a ritual context has long been the subject of speculation. In Moroccan traditional medicine, the ground seeds are used against subcutaneous tumours. Recent research has also demonstrated a significant anti-tumour effect of the harmala alkaloids from Peganum harmala in mice, an effect that could possibly be used in therapies for cancer patients (Lamchouri et al., 1999). Peganum harmala grows wild in Eurasia and has recently also been found in Texas, Nevada, New Mexico, and Southern California.

On account of the relatively low price and legal availability of these seeds, they are widely used outside South America for the preparation of ayahuasca analogues. In the Netherlands these seeds are available under the name Esphant in oriental shops. They are increasingly also taken in combination with psilocybin (4-hydroxy DMT)-containing mushrooms, a combination known as "shroomahuasca." Unlike DMT, psilocybin is also orally active without a MAO inhibitor, but its action is enormously potentiated by the addition of harmala alkaloids, probably through a combination of partial inhibition of the natural breakdown of psilocybin and the serotonin-specific reuptake inhibition of tetrahydroharmine described earlier. To obtain pure DMT, increasingly many people are busy collecting and analysing plants to isolate pure DMT, the prototype from this class. Various suitable plants grow in the Netherlands and the isolation procedure can be downloaded from the internet and in principle carried out by anyone at home. In recent years many people have come into contact with natural DMT.

Pharmahuasca is the name for ayahuasca based exclusively on pure substances. Jonathan Ott presents in Pharmahuasca a summary of his self-experiments with both crystalline N,N-dimethyltryptamine (DMT) combined with harmine, and combinations of other psychoactive tryptamines with other beta-carbolines (Ott, 1996). People wishing to experiment with these combinations are advised to inform themselves thoroughly beforehand.

The Legal Status of Ayahuasca

The harmala alkaloids are available in the Netherlands in the form of Peganum harmala seeds and are completely legal. Dimethyltryptamine, on the other hand, was placed at the beginning of the 1970s, along with a number of other "psychotomimetic" substances, on Schedule I of the Controlled Substance Act (CSA) of the Drug Enforcement Administration, US Department of Justice. Notably, this was done without further research. The reasons for placing DMT and other tryptamines on this list are therefore not as easy to trace as those for other substances on the list, such as heroin. The criteria for substances on this list are:

1. The drug or other substance has a high potential for abuse. What is probably meant here is primarily the addiction potential, which does not apply to DMT. Nowhere in the literature is there a single indication of the possibility of building a DMT or ayahuasca addiction. Tolerance to DMT has not been found. Dr. Jacques Mabit, the founder of the Takiwasi detox centre for addicts in the Peruvian Amazon, subsidised by the Inter-Ministerial Mission for the War on Drugs and Drug Addiction (MILDT) of the French government, has himself applied ayahuasca for a number of years and has observed its use among countless people. He writes that men, women, and children use ayahuasca and that in no case does it cause addiction (Mabit, 1996). While ayahuasca produces strong effects, he and the members of the research team have never seen an "ayahuasca addict," and according to him an ayahuascero actually needs less and less ayahuasca over time. On the contrary, ayahuasceros use ayahuasca precisely to help drug addicts off their addiction (Mabit, 1996).

2. The drug or other substance has no currently accepted medical use in treatment in the United States. In the United States, but also in other countries, the number of people, including doctors, psychiatrists, and psychologists, who use ayahuasca is growing. A relatively large proportion of members of the Uniao do Vegetal, for example, have such a background and are convinced of the powerful therapeutic action of ayahuasca.

3. There is a lack of accepted safety for use of the drug or other substance under medical supervision. The risks of ayahuasca use are reduced to a minimum in an adequate and controlled setting. Most entheogens have a large margin between a psychoactive dose and a toxic or harmful dose. The beta-carbolines and DMT in ayahuasca also have a large therapeutic window. The safety of entheogen use under medical supervision was also clearly demonstrated. A literature review of all scientific experiments with entheogens found that panic and other negative reactions are extremely rare, and it was concluded that the risks relative to the potential value are small (Strassman, 1984). As early as 1962, a report by the Inspectorate for Mental Health concluded that entheogen-assisted therapies under appropriate supervision are no more dangerous than other forms of therapy (Meijering, 1962).

With entheogens, set and setting have an especially strong influence on the quality and direction of the experience. Set refers to mood, expectations, personality factors, genetic and other factors directly belonging to the person. Setting encompasses the situation and environment in which one uses, when, and with whom. What is generally understood as medical supervision is not an ideal setting. For therapeutic effect to be achieved and measured, the wellbeing during the experience is of great importance. Experienced users will therefore prefer a different setting.

The placement of (components of) ayahuasca on Schedule I of American drug law is in no way adequate. The same applies to most other entheogenic substances on Schedule I. Increasingly, a change in legal status is being advocated, because it is precisely the undifferentiated legislation that has negative consequences for society. Another aspect of the legal status of ayahuasca concerns plant rights. In 1996, the American Loren Miller of the International Plant Medicine Corporation obtained a patent on Banisteriopsis caapi after taking the plant without permission from the garden of an Ecuadorian family. The patent gave him the exclusive right to cultivate and sell new varieties. The indigenous population and several organisations in various South American countries protested, and subsequently saw their relations with America deteriorate. The US Patent and Trademark Office did recognise the inadequacy of American legislation and declared Miller's patent invalid in 1999. This was a major victory for the traditional societies in South America in which entheogenic plants are used.

Chapter 2: The Traditional Context of Ayahuasca Use

With the rise of a renewed interest in entheogenic substances, interest in shamanism has also grown strongly again. The number of publications on shamanism has increased sharply since Weston La Barre's republished dissertation The Peyote Cult in 1969 (La Barre, 1938, 1969). Characterised by hysteria, ecstasy, magic, and transvestism, shamanism has always been a subject difficult of access for the rational and positivist worldview of science. Here anthropology has been no exception and has generally failed to recognise the importance of shamanism as a dynamic force in the world, and to develop adequate analytical models for better understanding (Langdon, 1992). Entirely different worldviews from the modern Western one have emerged in this context. For a modern therapeutic application of entheogens, it is useful to look at the worldview, concepts, and practices of the specialists. Knowledge of shamanism gives the therapist a more comprehensive and adequate interpretive framework for entheogenic experiences.

Shamanism

Historical shamanism goes back at least several thousand years and forms what is probably the oldest religious or spiritual practice of humanity. The word saman (shaman) comes from the language of the Tungus tribe of Siberia, where it functions both as a noun and a verb, referring to the work the shaman performs rather than a movement or name of a religion. In general, shamanism is described by anthropologists as an archaic magical-religious phenomenon in which the shaman is the master of ecstasy (Eliade, 1951). Although not all techniques and experiences are ecstatic, mastery over ecstasy is seen by many as the primary and most characteristic feature of the shaman.

According to Eliade, we find the pure form of shamanism primarily in Siberia and Central Asia and in near-pure form in the New World. Harner defines the shaman as a man or woman who stands in direct contact with the spirit world and has one or more spirits under their command to carry out their request or command for good or evil (Harner, 1973). An anthropological handbook describes the central features of the shaman as follows: possessing special skills, talents, or knowledge that make it possible, for example, to communicate with spirits, heal illnesses, and perform magical acts; tracing this knowledge back to contact with the supernatural; acting as an individual in dealings with the supernatural as speaker or representative of their group; and the absence of membership of formal, bureaucratic religious organisations (Vivelo, 1981).

In the induced trance, the shaman leaves their body behind to travel freely through the heavens or underworlds, where they can communicate with spirits without interrupting their own flow of consciousness. This makes it possible to bring knowledge across the boundaries of reality. Everything the shaman does is determined by these experiences and this knowledge. Their personal experiences and the knowledge that flows from them enable them to maintain established links between separate worlds. A true shaman can even simultaneously perceive different realities, perform magical actions within them, and from there influence other realities. They can use their skills to heal illnesses, control the elements, predict the future, gather information about distant places, retrieve lost objects or souls, or as a "psychopomp" guide the souls of the deceased to their place in the next world.

Authentic forms of traditional shamanism have now almost entirely disappeared. There are many shamans in South America who can no longer find a successor to continue the tradition. The young men from their culture are increasingly adopting a "Western" lifestyle. Other factors that have pushed shamanism back in recent decades are the work of Christian missionaries and laws enacted by governments (Harner, 1973). Anthropologists fear that shamanism in its original form is doomed to disappear rapidly, along with the unique lifestyle and skills that differ so strongly from those of "modern" man. Modern shamanism is usually based on old traditions but is primarily a practice that aligns with current Western notions. These modern forms of shamanism emerged from a combination of interest in nature, popular anthropology, and the need for a more open and less institutionalised form of religion and spirituality.

Plants within Shamanism

No matter whether we believe that men's intake of hallucinogens in primitive or sophisticated societies constitutes use, misuse, or abuse, hallucinogenic plants have undeniably played an extensive role in human culture and probably shall continue to do so. It follows that a clear understanding of these physically and socially potent agents should be a part of man's general education.
-- Schultes, R.E. (1976): Hallucinogenic Plants

Shamans use various methods to induce a trance, such as fasting, percussion, dance, and song, but also by ingesting entheogens. The use of entheogens can be found in a large number of cultures worldwide. Richard Schultes and Albert Hofmann describe this universality in the preface to their book Plants of the Gods:

These plants have been known and employed in human experience since earliest man's experimentation with his ambient vegetation.... They have long played an important role in the religious rites of early civilizations and are still held in veneration and awe as sacred elements by certain peoples who have continued to live... bound to ancient traditions and ways of life. How could man in primitive societies better contact the spirit world than through the use of plants with psychic effects enabling the partaker to communicate with supernatural realms?
-- Schultes and Hofmann, 1979

In Africa, Tabernanthe iboga is used within the Bwiti cult (Leenders, 1999). The use of Cannabis is found throughout the north of the continent. In Algeria, prehistoric rock paintings were discovered indicating a mushroom cult fully developed as early as 6000 BCE (Ripinsky-Naxon, 1993). In Asia, Cannabis and Datura occupy an important place in various religious movements (Heinrich, 1998). It is now also clear that Soma, the ritual drink that receives much attention in the early Vedic writings of Hinduism, is an entheogen and probably a mushroom (Ruck, 1982, 1983). In China, cannabis use dates back to almost 3000 BCE. Indian medical texts older than 2000 years describe therapeutic applications of Cannabis. In Papua, various plant substances are combined to achieve an effect; for this purpose the bark and leaves of the Agara tree (Galbulimima belgraveana) are cooked together with leaves of Ereriba (Homalomena species). In Europe, witches in the Middle Ages took nightshade plants such as Datura, Mandrake, Henbane, and Belladonna (Schultes, 1976). There are also many indications for a religious use of plants in the ancient Mediterranean cultures (Russell, 1998).

The largest number of psychoactive plants used, including those for ayahuasca, is found in the western hemisphere. Schultes writes in his richly illustrated book A Golden Guide: Hallucinogenic Plants:

It would not be an exaggeration to say that some of the New World cultures, particularly in Mexico and South America, were practically enslaved by the religious use of hallucinogens, which acquired a deep and controlling significance in almost every aspect of life.
-- Schultes, 1976, p. 56

In Mexico we find the use of the peyote cactus, the magic mushrooms, and the seeds of morning glories, which also played important roles among the Aztecs and were known respectively as Peyot, Teonanacatl, and Ololiuhqui (Bergmanns, 2000). Today, at least 24 mushroom species are still used in southern Mexico (Schultes and Hofmann, 1980), for example among the Mazatecs (Wasson et al., 1974). The Andean highlands and the Amazon basin in South America also display a particularly great diversity of entheogenic plants, including the ritual use of Brugmansia species, San Pedro cactus, tobacco, and a large number of other plants with entheogenic action. Other widely used plants with an important function within shamanism there are the plants containing DMT and beta-carbolines. In addition to incorporation in ayahuasca, DMT-containing plant mixtures are snuffed by various tribes, for example epena among the Yanomamo of southern Venezuela and northern Brazil, and hakudutha obtained from Virola among the Yekwana Indians of Venezuela (Schultes, 1976).

The importance of entheogenic plants in the shamanic practice of many Indian tribes of the upper Amazon is unmistakable. For the Yagua, for example, making contact with the plant spirits by ingesting the plants is even the only path to knowledge (Chaumeil, 1983). Among the Shipibo Indians, the relevant plants are referred to by the term muraya cal, meaning roughly "shaman-maker" (Gebhart-Sayer, 1986). These plants show reality while normal reality is considered an illusion (Chaumeil, 1983; Langdon, 1979b; Harner, 1972). In the area around the upper Amazon, the ingestion of entheogenic plants, and primarily ayahuasca, is the most commonly used way to enter a trance state (Langdon, 1992).

A possible explanation for the undervaluation of entheogens in the earlier literature is the fact that researchers had not themselves undergone the effects (Harner, 1973) and had attributed a symbolic function to these substances in analogy with, for example, the host in the Catholic Church. Eliade thought that the use of entheogens within shamanism could only bring about a kind of degeneration of a pure, organic trance, which he believed was standard in primordial shamanism, and saw in these "drugs" only a vulgar substitute for the "pure" trance. Later, however, Eliade changed his view and came to the conclusion that there was no phenomenological difference between "spontaneous" and entheogen-induced trance, and that we are dealing with a very ancient shamanic practice.

Ayahuasceros

Like the use of other entheogens in traditional societies, ayahuasca is used primarily in religious and social contexts. In order to acquire and maintain supernatural contact, the shaman enters into a relationship with ayahuasca. Shamans who have been interviewed make it clear that the plants (spirits) are their teachers and transmit knowledge directly to the shaman (Luna, 1984). The senior shaman who teaches the novice only mediates in the knowledge transfer, protects them from black magicians and evil spirits, and provides the adequate conditions under which the transmission of knowledge is possible.

Although there are differences between the concepts and practices of different groups in South America, the worldview of the often widely separated tribes corresponds strongly. The cosmos is seen as a reality built up of different layers in which everyday reality is accorded the least reality value, or is even regarded, as among the Jivaro, as a lie (Harner, 1972). These different layers are connected by a general principle of energy and form a whole in which everything is related to the cycles of production and reproduction, life and death, growth and decay. The shaman, through their dealings with ayahuasca, has acquired the power to form a bridge within the system of energy between the different layers of reality (Langdon, 1992).

The most important skill of an ayahuascero is the singing of icaros, the magical songs with which the shaman can strongly influence the course of the session. The magical songs are sung only during ayahuasca sessions. The power of a shaman is measured in part by the quantity and quality of icaros they have received from the plant spirits. The icaros give structure to the visions and have a strongly modulating effect on the energy distributions during the sessions. Another frequently described technique in the work of the ayahuasceros is the removal of magical objects from the body of the patient. A widespread representation of the causes of illness is that another shaman has shot a magical arrow into the body of the patient. The only way to solve the problem is to remove this arrow from the body. The shaman, for whom the body of the patient is transparent during the trance, bends over the place where the arrow is located, sucks it out of the body, and then spits it out. As proof of their magical action, they show the patient a symbolic object.

Shamanism and Western Psychotherapy

Today, aspects of shamanism are also being integrated into their work by psychotherapists in the Netherlands. Not much has been written about the points of contact and differences between psychotherapy and shamanism. It is clear that the uninformed use of shamanic techniques within psychotherapy will lead primarily to a disruption of the psychotherapeutic process. Metzner describes four paradigms in which aspects of shamanism, including the use of entheogens, can be combined with Western therapeutic techniques:

• Psychedelic psychotherapy within the context of the Western standard paradigm. Here entheogens are used to intensify the process of self-analysis and self-understanding.
• Shamanic rituals for healing and prediction. Here the therapist primarily uses the entheogen to see causes of and possible treatment for an illness.
• Syncretistic religious ceremonies where the emphasis is on a sense of community and communal worship.
• The hybrid shamanic-therapeutic rituals, in which aspects of the first two paradigms are combined.

Metzner writes that the shamanic and hybrid shamanic visions differ radically from the accepted Western worldview on two points: first through the assumption (and observation) of multiple realities that can be explored in an expanded state of consciousness, and second through the belief that the beings one encounters in dreams and visions are just as real as beings in physical reality (Metzner, 1998).

According to Marlene Dobkin de Rios, however, the differences between shamanism and Western psychotherapy are enormously large. She sees, among other differences, the absence of transference effects in short-term ayahuasca treatments, which occupy a very important place in Western psychotherapy (Dobkin de Rios, 1972). In an article from the Dutch journal Bres (winter 1998/1999), the differences between traditional shamanic techniques and Western psychotherapies are summarised:

Time versus space, gradual development versus sudden change. Western therapy takes place in linear time. A therapeutic process has a certain duration of several weeks to several years. For a shamanic healing, often a single or few sessions are sufficient to have an effect, and distance from time is taken instead. The healing takes place within a timeless mythical space in which directions and spatial relationships become more important. Shamanic healing requires a minimum of time compared with Western therapy.

Active guidance versus passive support. A therapist in the West is usually actively involved in the healing process of the patient, actively guiding and making choices about how the therapeutic process should proceed. In Western forms of psychotherapy, words generally play a central role in the healing process. According to Marlene Dobkin de Rios, this emphasis on the verbal in Western psychotherapy contrasts sharply with the techniques from a society where magic plays a large role (Dobkin de Rios, 1972). The shaman speaks very little during the session and is mainly concerned with creating the right circumstances and maintaining the spiritual topography of the universe within which the healing takes place.

Power from within versus power from without. In the Western therapeutic process, the emphasis is placed on skills that lie within the person themselves. These are changed, developed, or unlearned. In shamanic practice, attention is directed outward. Spirits from outside are invoked to help the patient (van Kampenhout, 1998).

Besides these and other differences, shamanism developed in an environment where people live in connection with nature. Modern Western forms of therapy are made for patients who generally have much less or no connection with nature and live in an artificial environment (van Kampenhout, 1998). Therapists who want to integrate the use of ayahuasca or other shamanic elements into their practice must inform themselves well and be aware of the mentioned differences between shamanism and Western therapeutic forms. For an application of ayahuasca in the West, it is actually a requirement that the therapist themselves has sufficient experience with the action of entheogens.

Chapter 3: More Recent Developments in South America

The use of ayahuasca is a phenomenon spread across the entire Amazon region. The countries in this region have undergone strong socioeconomic changes in recent decades. Extreme exploitation of the jungle, capitalism, and large-scale migration flows from the Andes and coastal areas have left clear traces. Many of the groups living traditionally have disappeared as a result of these influences; others have modernised (Luna, 1991). The anthropologically pure traditions survive only among Indian tribes in areas far from cities. Nevertheless, knowledge of the religious and therapeutic value of ayahuasca was partly preserved and is applied in various modern contexts.

Curanderismo

Today we find the use of ayahuasca in South American cities, where mestizo curanderos treat various illnesses. Patients seek out curanderos because they do not trust Western medicine, cannot afford it, or have had no success with previous attempts. According to a survey, 25% of mestizos prefer curanderos to Western-oriented medicine. According to Dobkin de Rios, the influence of curanderos is even greater (Dobkin de Rios, 1972).

Many mestizos in cities suffer, due to their situation often characterised by annual flooding of their homes, lack of sanitation, unemployment, and resulting intra-family conflicts, from anxiety and other stress-related psychosomatic conditions (Dobkin de Rios, 1984). The curanderos working in Iquitos and the surrounding area make a large contribution to reducing these conditions. The curanderos also give meaning and coherence through their work to various belief systems, remnants of Indian worldviews that have generally disappeared or been disrupted by Western civilisation processes (Luna, 1984).

As in the traditional belief systems, the causes of illness within curanderismo are seen as magical in nature, especially when identifiable causes at the physical level are absent. According to Dobkin de Rios, who conducted conversations with patients and curanderos, the patient is rarely held responsible for the causes of their illness. Illness and misfortune are much more attributed to the malice of others or to uncontrollable natural forces punishing a person who has broken a taboo (Dobkin de Rios, 1972). Within mestizo healing sessions, ayahuasca is therefore applied primarily with the intention of discovering magical causes, recognising and neutralising evil spirits held responsible for a particular condition. Within the context of a shared magical worldview, the curanderos prove able to treat many illnesses successfully (Dobkin de Rios, 1984). Particularly what would be called psychosomatic conditions in the West appear to be well treatable with ayahuasca.

The curanderos in the cities can be subdivided into different groups. The vegetalistas, the plant specialists, differ from the oracionistas, shamans who work with prayers, and the espiritistas, who work primarily with spirits. The vegetalistas are further subdivided into various subgroups including the purgueros, who mainly apply ayahuasca in their work. The tabaqueros use the strong mapacho tobacco and the perfumeros bring about therapeutic effects with the essence of flowers. Like traditional shamans, the more modern vegetalistas also indicate that they have obtained their knowledge and power with the help of the plant spirits and have in part never trained with another shaman. The plant spirits manifest during the visions and dreams of the vegetalistas and indicate which illnesses are involved, which plants should be used in which way, and how the cause of an illness should be removed from the patient's body.

A Session

Healing sessions take place outside the city in an open space in the jungle (Dobkin de Rios, 1970), where the rituals are not disturbed by traffic and other city noises. The curanderos also fear problems with police if they sing icaros in the cities. While according to Peruvian law it is legal to take natural consciousness-altering substances, the work of a curandero without a licence is prohibited (Dobkin de Rios, 1972). Between four and thirty persons take part in these regularly held sessions. The patients gather in the evening, present small gifts to the curandero, and sit in a circle to keep away evil spirits. Patients with a serious organic condition or a psychosis are referred for medical treatment in Iquitos. The curandero determines the dose based on among other things body weight, general constitution, experience with ayahuasca, and the nature of the illness. After individual protective blessings, the cup of ayahuasca is passed around, with the curandero always drinking last (Dobkin de Rios, 1972). Some must vomit, which is seen as normal or even as a good sign of physical cleansing. Urban curanderos also use icaros in Quechua, the schacapa rattle, the blowing of tobacco smoke over the body to guide the visions, and suction of magical objects from the body of the patient (Dobkin de Rios, 1972). The shaman shares with the patient what forms of prayer, penance, and apology are necessary to recover completely, often accompanied by advice on behaviour regarding diet, hydrotherapy, phytotherapy, and comparable natural medicine. In some cases Western biomedical techniques are also included in the treatment (Joralemon, 1993).

Ayahuasca Churches

Another recent development around ayahuasca in South America is the emergence of ayahuasca churches. Within these churches, the ritual use of ayahuasca is the most important sacrament. The best known of these movements are the Santo Daime and the Uniao do Vegetal, both originating in Brazil. These syncretic churches, so called due to the blending of Christian and shamanic concepts, have by now also established themselves in other countries and have largely contributed to the spread of ayahuasca use outside South America. Interesting for this thesis is that many members of these churches were formerly addicted but now, through their relationship with ayahuasca within a ritual setting, lead a sober and respectable life (Yensen, 1996).

a. The Santo Daime

Raimundo Irineu Serra was a rubber tapper from the state of Acre in northern Brazil. Serra had been raised Catholic and had probably come into contact earlier in his life with Spiritism and traditional Indian worldviews. In the 1920s Serra took ayahuasca for the first time after having gained more intensive contact with the Indians through his work. At a certain moment, under the influence of ayahuasca, the queen of the forest appeared to him, whom he recognised as the Virgin Mary (MacRae, 1992). She gave him the task of using ayahuasca in a special way, with specific rituals and songs that would be transmitted to him (Richman, 1990). The queen of the forest appeared again and again in his visions to teach him how to use ayahuasca as a sacrament and to support him in founding the community. Besides the visions, Serra received hymns that would form the liturgy of the new church. The teachings that arose from this are directed at healing and enlightenment. Various hymns relate to ayahuasca as teacher, the Virgin Mary and other Christian elements, reincarnation, and redemption. These hinos were collected in a hymnal and according to the followers constitute a kind of third testament (Richman, 1990).

Serra moved in the 1930s from the rainforest, where he had gathered followers among the rubber tappers and other primarily poor and black country people, to the small town of Rio Branco. Here in 1940 he established his church under the name Alto Santo. Subsequently, the teachings of the Alto Santo penetrated to most of the important urban areas in Acre. Serra received increasingly more hinos during this time. The frequency with which Daime, the imperative of the verb "to give" in Portuguese, occurs in these hymns led to Santo Daime as a new name for the religion. Serra died in the early 1970s and the church was subsequently led by his successor, Sebastiao Mota de Melo, known as Padrinho Sebastiao. Problems with the Catholic Church led in the early 1980s to Sebastiao moving the main centre of the Santo Daime to the remote village of Ceu do Mapia (the heaven of Mapia). Here several hundred followers gathered to lead a simple and ecologically conscious life without money and electricity, in harmony with nature.

The Santo Daime has grown significantly since then, finding followers in many countries. In 1989, the various groups established a central Santo Daime institute, the CEFLURIS (Centro Ecletico da Fluente Luz Universal Raimundo Irineu Serra). The current leader is Sebastiao's son Alfredo Mota de Melo.

The Ritual Practice of the Santo Daime

The Santo Daime has various types of rituals. The Hinario takes place on Catholic feast days and on the birth and death anniversaries of important Santo Daime leaders. During this festive ritual the hinos received by a single person are generally sung; the Hinario Irineu consists of the approximately 130 hymns that Irineu received during his lifetime. The Hinarios last between 6 and 10 hours and generally take place between sunrise and sunset. Several times during the day ayahuasca is drunk, though at a lower concentration for the Hinarios. The participants stand in a row from smallest to largest and dance the Bailado, a simple dance step that is performed in one of three variations depending on the accompanying hymns. According to the daimistas, the Bailado sets a flow of energy in motion among the participants in the ritual (Richman, 1990).

Another ritual, the Concentracao, is held on the fifteenth and thirtieth of each month. Here participants do not dance but sit with straight backs and upright heads, with arms and legs uncrossed to avoid blocking the energy flow in the body. This ritual form is more meditative, with silences allowing a more individual journey through the altered states of consciousness. A third characteristic ritual is the Star Work, in which the therapeutic process plays a central role. For this, a more strongly dosed ayahuasca tea is served. Women and men are equally distributed in the group and sit separately from each other in a circle around seven experienced Daimistas who sit around a star-shaped altar. On the altar stand various images, including those of deceased Daimistas, Jesus, and Catholic saints, alongside crystals, incense, and candles (Groisman and Sell, 1995).

Santo Daime in the Netherlands

The legal situation in countries where the Santo Daime has recently established itself is not as open as in the country of origin. After the churches were able to hold their services for a few years without problems, some Daimistas came into contact with police in the past year. From October 1999 onwards, various police actions took place in several European countries. After the German Santo Daime was first harassed, a raid was conducted in the Netherlands during an ayahuasca ritual. The responsible Dutch Daimistas were accused of being members of a criminal organisation and distributing the prohibited substance DMT. The two Dutch leaders were, however, able to leave prison two days later. Ten days later, the leaders of the French Santo Daime were arrested and imprisoned for three weeks. The case received much less publicity in France than in the Netherlands, where newspapers reported on the issues and a demonstration for the legalisation of ayahuasca took place in December 1999.

In response to the legal problems, the European Daimistas drew up a plan to achieve recognition as an official religion and the legalisation of ayahuasca. In March 2001, the two heads of the Dutch Santo Daime appeared in court. The ayahuasca seized during the police raid was examined in a laboratory and found to contain 0.02% of the prohibited substance DMT. The Public Prosecution Service emphasised the possible negative effects of the tea. That the physical reactions are not caused by DMT but by the legal beta-carbolines, and that they are an important part of the therapeutic process that ayahuasca sets in motion, apparently escaped notice. The lawyer for the Santo Daime had consulted a broad spectrum of experts on the effects of ayahuasca in a ritual context. The experts unanimously concluded that DMT poses no threat to public health. According to the lawyer, the police, with the raid during the Santo Daime ritual, had violated the law on religious freedom. Some believe this anti-ayahuasca action was prompted by pressure from the American government, which continues to try to export its drug hysteria to other countries.

The Uniao do Vegetal

The Uniao do Vegetal was founded in the 1960s by the rubber tapper Jose Gabriel da Costa, who had come to know the effects of ayahuasca and was greatly impressed by the magical properties of the plant mixture. The belief system of the new church emerged from a combination of early mythology, belief in jungle gods and spirits, and Catholic elements. Today the Uniao do Vegetal, with more than six thousand members and more than fifty separate nucleos, is the largest ayahuasca church. Unlike the Santo Daime, which has split into eight or nine different sects, the Uniao do Vegetal has only one, the Uniao. The thousands of members come primarily from the richer middle class and consist of a relatively large proportion of doctors, judges, politicians, bankers, and other comparably highly educated individuals.

In the literature on ayahuasca, a 1994 study is often cited in which members of the Uniao do Vegetal who had been drinking ayahuasca for at least ten years were compared with a control group of people who had never previously used ayahuasca. The UDV members achieved significantly higher scores on various psychological tests, were successful, and felt more certain, cheerful, and calm than before their entry into the Uniao do Vegetal. They also scored significantly higher on measures of concentration, short-term memory, and emotional maturity than the control group. Importantly, the members who regularly participated in the rituals after initiation lead a sober life. 73% of the members had a history of significant alcohol use before joining the UDV, 33% including aggressive behaviour; 27% used stimulants, and 53% had a nicotine addiction. In interviews, most members described their life before their personal transformation in the Uniao do Vegetal as disrespectful, impulsive, aggressive, irresponsible, and unsuccessful (Grob, 1999). Through their relationship with ayahuasca, a complete change in behaviour and in norms and values had taken place in most members. Members also reported sustained positive mood and satisfaction in everyday dealings with people, and a sense of purposefulness, meaning, and coherence in their lives. Ayahuasca was described as a catalyst for their moral and psychological evolution (Grob, 1999).

Another important result of the study is that UDV members have a greater number of serotonin receptors on their blood cells than normal, the first time that such a change was brought about by a substance. This could mean that ayahuasca is possibly effective in the treatment of addictions associated with certain serotonin receptors. Grob emphasises, however, that ayahuasca should not be given to people like an ordinary medicine, and that set and setting factors, such as integration within the group, are enormously important (Grob et al., 1996).

The Ritual Practice of the Uniao do Vegetal

Within the Uniao do Vegetal, hoasca is taken only in a ritual context, with sessions taking place every two weeks. At the beginning of a session the mestre gives ayahuasca to each participant; in contrast to the Santo Daime, this is the only dose given. The participants then sit with closed eyes and with background music, waiting for visions and the cleansing effect of ayahuasca. The next level, in which spiritual cleansing takes place, is called miracao. This is an expression of the power aspect of hoasca and is attributed to Banisteriopsis caapi, the masculine component of ayahuasca. The visions of the miracao are, however, seen more as a kind of distraction from the true message, becoming less intense as someone gains more experience with ayahuasca. Consciousness then becomes very clear and a special interaction between the members and with the mestre takes place. The content of this period during a session is considered a manifestation of the light aspect and is attributed to Psychotria viridis, the feminine component.

Chapter 4: Therapeutic Applications of Entheogens

In the early twentieth century, doctors tried to strengthen the therapeutic effects of hypnosis and psychoanalysis with sub-narcotic doses of barbiturates. In this narcoanalysis, patients had better access to forgotten and suppressed material (Horsley, 1943), especially in the treatment of people with war trauma (Grinker, 1945).

The greatest part of early scientific research in the field of hallucinogens concerns LSD. After its psychoactive properties were discovered in 1943, attempts were made to map the effects of this unknown but promising substance. In the first clinical studies, the psychodynamic component of the LSD experience became clear (Stoll, 1947). After this publication, psychotherapists began to apply hallucinogens in their work (Busch and Johnson, 1950; Frederking, 1955; Chandler and Hartmann, 1960). Two important forms of entheogen-directed therapies were subsequently developed.

Psycholytic Therapy

In 1953, Sandison opened the first LSD clinic in England in a small psychiatric hospital. According to him, LSD in combination with psychotherapy was a particularly effective method (Sandison et al., 1954). The results of a follow-up study in which 94 psychiatric patients were treated with LSD were spectacular: 65% of the patients had recovered or improved. It was concluded that an LSD treatment strongly shortens the time needed for a complete psychological analysis (Sandison and Whitelaw, 1957). Sandison used an LSD dose of between 75 and 300 mcg, administered with intervals of one or two weeks in an average of forty sessions. In his psycholytic therapy, an extension or modification of psychoanalytically oriented psychotherapy, traumas from childhood are resolved and the patient gains valuable insights through emotional abreaction and integration of the experience (Grof, 1980).

Psycholytic therapy gained more and more followers in the course of the 1950s. Passie shows that between 1953 and 1968 more than 7000 patients underwent some form of psycholytic therapy (Passie, 1997). By the mid-1960s, eighteen centres in the Netherlands, Germany, Denmark, England, and Czechoslovakia were affiliated with the European Medical Society for Psycholytic Therapy (Grinspoon and Bakalar, 1997). Most therapists using entheogen-assisted therapy reported long-term improvement for two thirds of the generally severely or chronically neurotic patients (Brill, 1967).

Psychedelic Therapy

Another early development in the field of entheogens at that time was psychedelic therapy. The underlying theory assumes that a single overwhelming and profound psychedelic experience can bring about personal changes that can work through for months and years (Sherwood et al., 1962). Osmond, using this method based on the work of A.M. Hubbard, in which a high dose of LSD (300 mcg and more) was applied alone or in combination with other psychedelics, successfully treated chronic alcoholics. Often a single session was sufficient (Osmond, 1957).

Grof writes that his LSD patients who had experienced cosmic unity often developed a negative attitude toward the states of consciousness produced by alcohol and narcotics. In the Spring Grove studies there was a clear tendency among alcoholics and heroin addicts to stop their addictive behaviour after a single LSD session. In another setting at the psychiatric research institute in Prague, where multiple sessions were possible, lasting abstinence and profound personal restructuring were achieved among alcoholics and heroin addicts. After such an experience, drug abuse and suicidal tendencies were seen as serious errors, based on not recognising and understanding a spiritual longing for transcendence. In the Spring Grove research, alcoholics and heroin addicts had a greater chance of mystical experiences than all other investigated persons, such as neurotics, healthcare workers, or dying patients (Grof and Halifax, 1977).

	Psycholytic Therapy	Psychedelic Therapy
The Technique	Initiating and deepening psychoanalytic processes with a low dose of LSD (30-200 mcg) through production of symbolic dream images, regression, and transference.	Establishing cosmic-mythical experiences through administration of a high dose of LSD (300-800 mcg). The sense of unity, ecstatic joy, and profound existential insights are the result.
Underlying Concept	Psychodynamic interpretive framework.	Not based on classical psychological theories. New transpersonal approaches to explain the structure and effects of the experience.
Number of Sessions	10-50	1-3 convincing experiences
The Therapeutic Process	Analytical discussion of the experience in individual and group sessions, with emphasis on ego psychology, transference, and defence mechanisms. Striving to apply what has been learned to daily life.	Strong suggestive quasi-religious preparation. Application of the entheogen within a specific setting to structure the experience. No psychodynamic interpretation. The psychedelic experience stimulates change in attitude and personality.
The Goal	Healing through restructuring and maturing of the personality and the relieving of infantile bonds with parents. Intrapsychic and social harmony.	Behavioural change, symptom healing, and better social adjustment through a conversion-like existential experience and increased self-knowledge.

(Passie, 1997)

It should be noted that the division into only two paradigms is insufficient. In the scientific literature, the application of entheogens in psychotherapy was designated by a number of different names, including psycholysis (van Rhijn), hebesynthesis (Abramson), lyserganalysis (Giberti and Gregoretti), oneiroanalysis (Delay), LSD analysis (Martin and McCririck), transintegrative therapy (MacLean), the hypnodelic treatment (Levine and Ludwig), and psychosynthesis (Roquet) (Grof, 1980).

Despite differences with regard to dose, frequency, total number of sessions, and the nature and intensity of psychotherapeutic interventions, certain characteristics recur across all these forms of entheogen-assisted therapy:

• The experience of expanded consciousness can provide not only therapeutic insights but can also bring about fundamental changes with regard to the self-concept and the worldview.
• There is agreement that set and setting are the most important determinants of the psychedelic experience. The entheogenic substances act as a catalyst or trigger.
• In contrast to other psychiatric medications or psychoactive substances, the personal experience of the therapist with entheogens is essential.
• The frequently occurring experiences of transcendent, religious, or transpersonal dimensions are promising and form a challenge for psychology and related disciplines (Metzner, 1998).

In the 1960s the number of people experimenting on the basis of one of the mentioned or related therapeutic models with LSD and other entheogens grew. In many reports, the claims from the early period received support: that LSD promoted and shortened the psychotherapeutic process, which would make LSD a valuable tool within psychotherapy. It also became clear that LSD was particularly suitable for certain patient populations that could be helped neither by psychoanalysis nor by any other form of therapy. Successes were reported in the treatment of neurotics, alcoholics, opiate addicts, sociopaths, criminal psychopaths, disturbed personalities, and people with deviant sexual behaviour. LSD was also praised for the effect it had on people with incurable diseases and on the dying. It not only reduced emotional and physical pain but also brought about a radical and positive change with respect to concepts of and attitudes toward death (Kast, 1963; Grof, 1994). By the end of the 1960s the number of scientific publications on the subject had grown strongly. Grinspoon and Bakalar write that in the more than one thousand clinical papers between 1950 and 1960, more than 40,000 patients are involved (Grinspoon and Bakalar, 1981).

The Netherlands

Experimentation with LSD also took place early in the Netherlands, where it was used among other things for therapeutic purposes. Jan Bastiaans was the first Dutch psychiatrist to apply entheogens, primarily LSD but also psilocybin, in his practice. From 1954 to 1961 he was chairman of the Psychoanalytic Institute in Amsterdam, and from 1963 to 1985 professor of psychiatry at the University of Leiden. Besides his Freudian background, he was an adherent of psychosomatic medicine. Until 1988 he was able to help many at the Jelgersma clinic in Oegstgeest, and became especially well known for his therapeutic success in the treatment of people with concentration camp syndrome. Rarely were more than seven treatments needed, and the average time the entire therapy lasted was only fifty hours. He came to the conclusion that LSD worked particularly well for patients with psychosomatic conditions and rigidity in their defence and coping mechanisms, patients with a concentration camp syndrome, and patients who had not achieved the predicted positive results after many years of psychoanalytic therapy (Snelders, 1999).

Cornelius H. van Rhijn was a psychiatrist who from 1953 in the psychiatric clinic in Brinkgreven, and from 1960 in his own practice in Enschede, treated almost one thousand alcoholics with LSD. He made a major contribution to the discussion around LSD therapy, which he believed was useful to resolve stagnant situations and infantile fixations, to obtain rapid results in emergencies, to reduce compulsive neurotic impulses, ego dominance, feelings of guilt, and isolation, to release suppressed material from the unconscious, and to learn more about psychoses (Van Rhijn, 1967).

Geza Arendsen Hein applied LSD beginning in 1959, inspired by Leuner and Sandison. The medical team of the Veluweland foundation in Ederveen, where he had worked since 1953, treated patients who had at least some insight into their disturbed mental state, a strong will to recover, and no acute psychoses. Hein claimed that patients under the influence of LSD exhibited a reduction of defence mechanisms, an intensive abreaction of suppressed emotional material, and a symbolic presentation of conflicts. Patients also gained insight through introspection into their inadequate attitudes and norms and values were restructured. Two years after completion of the project, two thirds of the patients were clinically improved or well improved (Hein, 1965).

The history of LSD in Dutch psychiatry is described in detail in Snelders, S. (2000), LSD-therapie in Nederland, Candide/Wrede Velde.

Research Criteria

The results of early research were, however, controversial and not infrequently produced through methodological impurities. In any case, all the research never led to a generally accepted statement about the therapeutic value of entheogens. The large amount of anecdotal material describing enormous effects of entheogen-assisted therapies should not, however, be ignored. That the claimed effectiveness for certain conditions has not been clearly demonstrated should be no reason to ignore entheogens. There is, for example, no form of psychotherapy for neurotics that has ever been able to prove itself under strict conditions (Grinspoon and Bakalar, 1985), and yet a large number of neurotics are treated with psychotherapy. The necessary results of the entheogen therapies require more research than was possible before the entire research line was halted in the early 1970s, due to the negative social and political climate toward these substances. Now a new period of entheogen research is beginning.

Important points of attention for the evaluation of research into therapeutic effects of entheogens were summarised by O'Brien and Jones, who presented their findings in 1994 at the symposium of the Swiss Academy of Medical Sciences celebrating the fiftieth anniversary of the discovery of the psychoactive action of LSD. These eight essential characteristics of adequate research into the therapeutic effects of entheogens are:

• A specific diagnosis for each patient before treatment begins
• A randomised assignment of patients to different treatment options
• A standardised form of therapy
• Use of severity measures for patients
• Information for patients with a specification of clear and honest possible risks
• Clarity about the importance of follow-up research
• Use of placebo control groups
• Blind, objective researchers to determine the diagnostic category and measure the effects of therapy on patients (O'Brien and Jones, 1994)

Many of the results of earlier entheogen research were not valid and not generalisable as a result of shortcomings with regard to the criteria described above. Today there is awareness of these possible weaknesses and efforts are made to conduct scientifically responsible research. Only the last requirement of blind researchers is difficult to realise, because the psychological effects of entheogens are enormous, and it quickly becomes clear to the researcher whether someone belongs to the experimental or the control group (Lukoff et al., 1990).

Recent Research

LSD and MDMA

The usefulness of MDMA (methylenedioxymethamphetamine) as support for therapeutic processes is described by various authors (Grinspoon and Bakalar, 1986; Greer and Tolbert, 1990). MDMA has antidepressant and anxiety-reducing properties and induces a subtle, controlled emotional experience characterised by relaxation, joy, and increased empathy. Anxiety reactions and defence mechanisms are reduced and disturbed perception, agitation, or confusion generally do not occur (Greer and Tolbert, 1986, 1990; Peroutka et al., 1988). Against these positive reports stand a growing popularity, illegal misuse (Beck and Morgan, 1986; Beck, 1990), and reports of possible neurotoxicity (Price et al., 1989; Grob et al., 1990).

One of the first new research projects was conducted in the period from 1988 to 1993 by members of the Swiss Medical Society for Psycholytic Therapy. In the context of an exceptional permit, it was possible during a period of five years to apply and evaluate psycholytic therapy using MDMA and LSD. In a follow-up involving 121 patients who had undergone an average of seven psycholytic sessions in the course of therapy, the success rate was again enormously high: nine out of ten patients described themselves at the moment of follow-up as slightly (25%) or well improved (65%). Quality of life improved for 84.3%; self-acceptance increased for 81.8%; autonomy increased for 67.8%; relations with family improved for 81%; anxiety about death decreased for 57.9% (Gasser, 1994). Also noteworthy is that during the therapy virtually no problems arose such as suicide, a psychotic reaction lasting more than 48 hours, or the necessity of admission to a psychiatric hospital (Gasser, 1994). The support of psychotherapeutic processes by means of LSD and MDMA in a controlled setting was shown to be a safe method.

Ketamine

In a recent study into the effects of ketamine-assisted psychotherapy for alcoholics, comparably exceptional effects were measured. Ketamine was originally used as an anaesthetic for horses and as a painkiller in the Vietnam War, where attending doctors were confronted with profound religious experiences among the soldiers. In sub-anaesthetic doses, ketamine induces psychedelic experiences, seen as the underlying therapeutic mechanism in ketamine-assisted psychotherapy for alcoholism. The results of this controlled clinical study showed a clear increase in the effectiveness of the standard treatment for alcoholics when it was supported by Ketamine Psychedelic Therapy (KPT). Total abstinence for longer than one year was found in 73 of 111 (65.8%) patients, while in the control group receiving conventional treatment this was the case in 24 of 100 patients (24%). In addition, positive changes in norms, values, and goals, as well as insights into the meaning of life and a higher level of spiritual development were observed in the experimental group. Biochemical measurements revealed that the pharmacological effect of the KPT affects the monoaminergic and opioid neurotransmitter metabolism involved in the development of alcohol addiction (Krupitsky and Grinenko, 1997).

Ibogaine

The roots of the Tabernanthe iboga plant from equatorial Africa are used in Gabon in low doses as a stimulant and in high doses during initiation into the Bwiti cult. In the early 1960s the American Howard Lotsof experimented with ibogaine on his drug-addicted friends. Five of seven friends stopped using drugs during that period. Lotsof founded NDA International as part of his humanitarian mission and to bring the pharmaceutical preparation Endabuse (ibogaine hydrochloride) to market. In the 1980s and early 1990s he obtained four patents for a rapid method to break or reduce addiction to narcotics, cocaine/amphetamines, alcohol, and nicotine. Enormous successes were also achieved with ibogaine in the treatment of addicts. While more research has been done on it than on ayahuasca, the treatment has also not led to a generally recognised treatment paradigm. Legislation is again responsible. Ibogaine has recently been appearing on the black market, and therapists, including in the Netherlands, apply ibogaine successfully, though usually underground.

Ayahuasca as an Addiction Interrupter

A growing number of people, laypeople and professionals, also claim an addiction-interrupting effect for ayahuasca. Many who now regularly use ayahuasca and lead a sober life were addicted to various drugs before they came into contact with ayahuasca. Today ayahuasca is applied in various countries to help people off their addictions, but also from other illnesses. Nevertheless, the relevant clinical studies that would clearly demonstrate the claimed effects of ayahuasca have never been conducted. Success rates as high as those described in the projects above are never achieved in mainstream care. These positive experiences and research results with LSD, MDMA, ketamine, and ibogaine clearly call for more and larger-scale research than is currently actually being conducted.

Takiwasi

Takiwasi is an experimental treatment centre for drug addicts in Peru where ayahuasca is used. Takiwasi means "the singing house" and refers to the icaros, which are also here the most important tools of the healer. In 1992, Takiwasi was founded by Michael Mabit, who trained with various shamans and now applies his knowledge in collaboration with other shamans. The aim is to help the patient off their addiction by teaching them to change their consciousness without harming themselves and to acquire a "spiritual" vision that gives strength and confidence. Nearly two thirds of the patients were treated for addiction to cocaine base paste. On average, the patients had been on drugs for ten to fifteen years and were in partly very poor physical condition at admission.

The treatment at Takiwasi relates to different levels of the patient and proceeds in various steps. Spirituality forms an important element in the treatment and is seen in Takiwasi as the highest level. In the first month, most attention goes to the physical level. Eight days of complete isolation are followed by fifteen days of partial isolation. Alongside abstinence from herbs, sugars, coffee, and pork, the patient may not come into contact with menstruating women or sick or new patients still in detoxification (Mabit, 1996). This isolation period is repeated every two months. In addition to multiple cleansing rituals, there are saunas and massages with medicinal plants, daily therapeutic conversations, and a healthy diet. The condition of the patient improves rapidly, so much so that even patients in very poor shape at admission become completely physically healthy within two months (Mabit, 1996).

Subsequently, attention shifts to the psychological-affective-emotional level, and the patient undergoes their first ayahuasca ritual. These weekly sessions bring the content of the unconscious to the surface and form the cornerstone of the entire treatment programme. Following the rituals, attempts are made both individually and in the group to integrate the content of the entheogenic experience. At the highest level, the life of the patient acquires a profound spiritual meaning. The ayahuasca sessions are compared with an accelerated self-analysis in which the patient sees and understands their problems and possible solutions themselves, which strengthens the willingness to change (Mabit, 1996). Besides the diet and the ayahuasca sessions, a range of other shamanic techniques tailored to the individual or to the whole group are also applied. These are in the course of treatment also combined with other techniques such as holotropic breathwork according to Grof's model, Bach flower therapy, group dynamics, and meditation (Mabit, 1996).

More than half of the patients discontinued treatment in the first three months against the advice of the therapist; a quarter fled within the first three weeks without discussing the decision with the therapist. Eighteen percent of the drug addicts ultimately completed the entire treatment programme with an average duration of nine months. Nevertheless, given that these are cocaine addicts, the success of Takiwasi is reasonably large. Three quarters of the patients came back to Takiwasi after completion for advice, help, or a cleansing treatment with plants. The people who followed the treatment to the end have a much better perspective for their lives than those who stopped earlier (Mabit, 1996).

Friends of the Forest

The Takiwasi detox centre in Peru is not the only place where drug addicts are treated with ayahuasca. The Friends of the Forest, an organisation in Amsterdam, has also developed a detoxification programme. The team consists of strongly motivated people with medical and therapeutic backgrounds, judges, sociologists, and volunteers who have undergone their own process with ayahuasca. Yatra da Silveira Barbosa, the founder of the Friends of the Forest, was herself addicted to heroin and cocaine for twenty years. All the help of people and institutions she had previously turned to, and a large number of therapies she had followed, were in vain. Only through the ayahuasca rituals did a strong emotional process get under way that ultimately helped her off her addiction.

The effectiveness of ayahuasca therapy for, among other things, depression, addiction, and psychosomatic conditions is attributed primarily to two important properties of the ayahuasca experience: abreaction and the cleansing of the soul (catharsis). Catharsis has not only a detoxifying and cleansing effect on the body but also works through to the psychodynamic level. Spiritual catharsis takes place at a deep level when ayahuasca frees one from negativity and personal "garbage" accumulated in life. The course of this process is largely determined by the willingness of the individual to let go of their egotistical behaviour and pride. Abreaction brings about a regression to the cause of the problem or trauma, through which the person gains insight into the connections. The person thereby gets the opportunity to free themselves from underlying behavioural patterns or to change them. The result of this process is often a liberation from guilt and fear. This opens the possibility of organising life in a more positive way.

In the experimental FOF Rescue Program, drug addicts are treated in a ritual setting with ayahuasca and other plants. Besides transpersonal, behavioural, and other therapeutic forms, the programme includes the use of vitamins and natural and traditionally used medicines. In the first three weeks, the detox period, patients are treated inpatient under special medical care. Subsequently, patients are treated outpatient for a period of three months. The last three months, patients are treated inpatient again. The Friends of the Forest have been treating drug addicts for some time. Due to a lack of funding, however, patients have until now only been treated on an outpatient basis. It is to be hoped that projects like that of the Friends of the Forest will receive more support in the future.

Summary

Ayahuasca, an entheogenic substance from the Amazon region, has been used for centuries, and is still being used, by shamans in South America. In the right context, it apparently has the potential to heal a range of conditions. Recently it has also gained a following in the Netherlands, and the number of people who have experienced the overwhelming effects of ayahuasca has grown strongly. Many describe positive therapeutic effects. Particularly interesting are the numerous claims that ayahuasca, when used in the right context, can break addictions to various substances. Among other things, it is applied with success in South America in the treatment of cocaine addiction, for which no effective therapy is known in the West. To this day, however, no generalisable studies have been conducted in this area. To a large degree, this has to do with the fact that ayahuasca contains DMT, which in the United States was placed on the list of the most strictly prohibited substances. The Netherlands concurs with this, even though a scientific foundation for the classification of DMT as a hard drug was never provided.

Church communities that have been holding rituals in the Netherlands for years have as a result recently run into problems with the law. Research into ayahuasca is also being hampered by these developments, and information about therapeutic effects remains largely limited to anecdotal material. Nevertheless, there is much about ayahuasca to be found that can contribute to such therapeutic application. In this thesis, contributions from various disciplines are set side by side. In the first chapter, the relevant plants for the preparation of ayahuasca and the active substances are described. In Chapter 2, the traditional use of ayahuasca in South America is described; shamanic concepts are better suited to the entheogenic experience than Western paradigms, making the knowledge of these experts relevant and worth consulting. Chapter 3 describes more recent developments in South America, including the emergence of urban curanderismo and the Brazilian ayahuasca churches. Chapter 4 covers research into therapeutic applications of entheogens, including the history of LSD, MDMA, ketamine, and ibogaine therapy, and the specific projects in which drug addicts are treated with ayahuasca.

Conclusions and Recommendations

Motivated by the claims of therapists who treat various conditions with ayahuasca, I began a survey of what is known about it. While much has been written about ayahuasca, little scientific literature about the effectiveness of such treatment can be found. The information from different disciplines that can contribute to further research into ayahuasca as a therapeutic agent has been brought together in this thesis. It becomes clear that research into the therapeutic effects of ayahuasca and other entheogens would make sense and is desirable. After all, in the Netherlands we also have drug addicts for whom no effective therapy exists.

Unfortunately, research is severely restricted by legislation. Dutch drug law is linked via international treaties to the American. The legislation on drugs in America has led to great damage to public health. The negative results are unmistakable and it seems as if nothing has been learned from the alcohol prohibition of the 1920s. The legislation has not been able to reduce use, but has created enormous obstacles for researchers who want to map the therapeutic value of entheogens. Ayahuasca, or rather the prohibited substance DMT, does not in any way meet the criteria for Schedule I. The placement of DMT and other entheogenic substances on Schedule I of the Opium Law is clearly unjustified. Professor Wolff of the Academic Hospital in Leiden says, as toxicologist and adviser to the Dutch Ministry of Health:

"this is a complicated judicial contradiction, and to be honest, no one has ever explained to me why these substances are on list 1 of the Opium Law in the first place. This applies, in my opinion, also for psilocin and psilocybin! We see a specific group of substances, mostly from botanical origin, that influence human consciousness, but don't have problematic side effects. We know from most of these substances that they are not addictive and people don't show withdrawal symptoms when they stop using these substances. I don't understand why such a fuss is made about substances that are even less harmful than marijuana."
-- OGD report, 1999

At the same time, other substances whose dangers to public health have been clearly demonstrated are entirely legal. Thirty percent of all cancer deaths are the result of legal nicotine use (NIGZ, 1999). In 1995, as many as 35,000 adverse reactions, including hostility, aggression, and hallucinations, and more than 2,300 deaths as a result of Prozac were already being reported. The financial burden on society and the damage to public health from legal smoking, drinking, and medication use are much, much higher than from all illegal drugs combined. This also applies to America, where enormous amounts of money have been and continue to be spent on a hopeless war against illegal drugs.

From a rational policy for maintaining public health, it is precisely some legal drugs that should be prohibited. For DMT, further research should in any case be conducted in order to be able to justify its illegal status. For a broad application of ayahuasca in therapeutic contexts, it would be desirable or even necessary for DMT to be placed on a different schedule.

Given the failure of American drug legislation with regard to its stated goals, the enormous costs of the war on drugs, and the social and personal damage that results, it is recommended to completely revise the drug legislation with regard to entheogens. If necessary, Dutch legislation should be decoupled from the American. It is strange that a country like the Netherlands is forced by old treaties with America to continue applying the undifferentiated and in no way empirically grounded legislation around entheogens and to bear its negative consequences. For the maintenance of a realistic approach to drugs in the Netherlands, fundamental changes must take place in this area.

It is also recommended to stimulate research into therapeutic aspects of entheogens and to draw up meaningful guidelines for them. Part of the current projects is now also being hampered by the changes in the Netherlands with regard to enforcement of the legal status of DMT.

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