Ayahuasca
Ayahuasca (Quechua, pronounced Template:IPA) is any of various psychoactive infusions or decoctions prepared from the Banisteriopsis spp. vine, native to the Amazon Rainforest (which is also called ayahuasca). The resulting drinks are pharmacologically complex and used for shamanic, folk-medicinal, and religious purposes.

## Preparation
Sections of vine are macerated and boiled alone or with leaves from any of a large number of other plants, including Psychotria viridis (chakruna in Quechua) or Diplopterys cabrerana (also known as chaliponga).  The resulting brew contains MAO inhibiting harmala alkaloids and the powerful hallucinogenic alkaloid N,N-dimethyltryptamine (DMT), a psychedelic which is active orally only when combined with an MAOI.  Harmala alkaloids in Banisteriopsis caapi serve as MAOIs in Ayahuasca.  Western brews sometimes substitute plant sources such as Syrian Rue or other harmala containing plants in lieu of the Banisteriopsis caapi vine, but the vine itself is always central to traditional usage.
Brews are also made with no DMT-containing plants; sometimes they are made with plants such as Justicia pectoralis, Brugmansia and sometimes made with no plants other than the ayahuasca vine itself. Tobacco is a common additive in traditional brews. The potency of this brew varies radically from one batch to the next, both in strength and psychoactive effect, based mainly on the skill of the shaman or brewer, as well as other admixtures sometimes added. Natural variations in plant alkaloid content and profiles also affect the final concentration of alkaloids in the brew, and the physical act of cooking may also serve to modify the alkaloid profile of harmala alkaloids.
Individual polymorphisms in the cytochrome P450-2D6 enzyme affects the ability of individuals to metabolize harmine. Some natural tolerance to the regular use of Ayahuasca (say, once weekly) may be seen as an upregulation of the serotonergic system. A phase 1 pharmacokinetic study on Ayahuasca (as Hoasca) with 15 volunteers was conducted in 1993, during the Hoasca Project. A review of the Hoasca Project has been published.

# Names
- "caapi", "cipo," "hoasca" or "daime" in Brazil
- "yage" or "yaje" (both pronounced Template:IPA)  in Colombia; popularized in English by the beat generation writers William S. Burroughs and Allen Ginsberg in The Yage Letters.
- "ayahuasca" or "ayawaska" in Ecuador, Bolivia and Peru, also to a lesser extent in Brazil ("vine of the dead" or "vine of souls": in Quechua, aya means "spirit," "ancestor," or "dead person," while waska means "vine" or "rope"). The name is properly that of the plant B. caapi, one of the primary sources of beta-carbolines for the brew.
- "natem" amongst the indigenous Shuar people of Peru.
The spelling ayahuasca is the hispanicized version of the name; many Quechua or Aymara speakers would prefer the spelling ayawaska. In the central Andeans of Peru, Ayacwasca means: "Ayac" (spirit or dead) and "Wasca" (vine, cord or rope)

# Usage
Ayahuasca is used largely as a religious sacrament, no matter which culture it is associated with. Those whose usage of ayahuasca is performed in non-traditional contexts often align themselves with the philosophies and cosmologies associated with ayahuasca shamanism, as practiced among indigenous peoples like the Urarina of Peruvian Amazonia.
While non-native users know of the spiritual applications of ayahuasca, a less well-known traditional usage focuses on the medicinal properties of ayahuasca. Its purgative properties are highly important (many refer to it as la Purga, "the purge"). The intense vomiting and occasional diarrhea it induces can clear the body of worms and other tropical parasites, and harmala alkaloids themselves have been shown to be anthelmintic.  Thus, this action is twofold; a direct action on the parasites by these harmala alkaloids (particularly harmine in ayahuasca) works to kill the parasites, and parasites are expelled through the increased intestinal motility that is caused by these alkaloids.
Dietary taboos are almost always associated with the use of Ayahuasca; in the rainforest, these tend towards the purification of one's self- abstaining from spicy and heavily seasoned foods, fat, salt, caffeine, acidic foods (such as citrus) and sex before, after, or both before and after a ceremony. A diet low in foods containing tyramine is recommended, as the interaction of tyramine and MAOIs can lead to a hypertensive crisis. This extreme dietary specificity is largely a modern one, as most tyramine is produced as food ages, and is therefore not usually a problem in traditional South American cultures. These dietary restrictions have developed as a means of making ayahuasca ingestion easier on the body, as well as having strong traditional and spiritual significance.
Today, the name 'ayahuasca' can mean a variety of botanical concoctions containing one or more MAOIs and DMT or one of its chemical analogues. The synthetic pharmahuasca is sometimes called ayahuasca as well. In this usage, the DMT is generally considered the main psychoactive active ingredient, while the MAOI merely  preserves the psychoactivity of orally ingested DMT, which would otherwise be destroyed in the gut before it could be absorbed in the body. Most ayahuasqueros and others working with the brew claim the B. caapi vine to be the defining ingredient; according to them, it is not ayahuasca unless B. caapi is in the brew. The vine is considered to be the "spirit" of ayahuasca, the gatekeeper and guide to the otherworldly realms.
In some areas, it is even said that the chakruna or chaliponga admixtures are added only to make the brew taste sweeter.  This is a strong indicator of the often wildly divergent intentions and cultural differences between the native ayahuasca-using cultures and psychedelics enthusiasts in other countries.
In modern Europe and North America, ayahuasca analogues are often prepared using non-traditional plants which contain the same alkaloids. For example, seeds of the Syrian rue plant are often used as a substitute for the ayawaska vine, and the DMT-rich Mimosa hostilis is used in place of chakruna. Australia has several indigenous plants which are popular among modern ayahuasqueros there, such as various DMT-rich species of Acacia.
In modern Western culture, entheogen users sometimes base concoctions on Ayahuasca.  When doing so, most often Rue or B. caapi are used with an alternative form of the DMT molecule, such as psilocin, or a non-DMT based hallucinogen such as mescaline.  Nicknames such as Psilohuasca, Mush-rue-asca, or 'Shroom-a-huasca, for mushroom based mixtures, or Pedrohuasca (from the San Pedro Cactus, which contains mescaline) are often given to such brews. Such nicknames are by many considered inappropriate and culturally insensitive seeing as "huasca" means "vine" and none of the above are vines, nor do the psychedelic experimentalist trappings of such concoctions bear any resemblance to the medicinal use of Ayahuasca in its original cultural context. This is usually only done by experienced entheogen users who are more familiar with the chemicals and plants being used, as the uninformed combination of various neuro-chemicals can be dangerous.
It seems unlikely that Ayahuasca could ever emerge as a "street-drug", given the difficulty of making the tea and the intense experience it provides.  Most Western users employ it almost exclusively for spiritual purposes, in line with both traditional, animist usage and organized churches such as the Uniao do Vegetal (or UDV).  A diet is almost always followed before use, including a day of fasting, to rid the body of tyramines and other contraindicated chemicals; a "dieta" is often followed as well, to spiritually cleanse the body before and after the experience.  Most recreational drug users have never even heard of Ayahuasca, or the possibility of alterations to the shamanic brew.

## Introduction to the West
Ayahuasca is mentioned in the writings of some of the earliest missionaries to South America, but it wasn't for some time that it became commonly known in the West.  The early missionary reports generally claim it as demonic, and great efforts were made by the Roman Catholic Church to stamp it out.
When originally researched in the 20th century, the active chemical constituent of B. caapi was called telepathine, but it was found to be identical to a chemical already isolated from Peganum harmala and given the name harmaline.
William Burroughs sought yage (still considered to be "telepathine") in the 1950s while traveling through South America, in the hopes that it could relieve or cure opiate addiction. The Yage Letters, written between Burroughs and Allen Ginsberg were probably the first major introduction of Ayahuasca to the West.
Ayahuasca was made more widely known by Terence and Dennis McKenna's experiences with Amazonian tribes as detailed in the book Invisible Landscape, which they co-authored. Their journey to the rainforest to search for Ayahuasca was spurred by their reading of Burroughs and Ginsberg.  Dennis later extensively studied the pharmacology, botany, and chemistry of ayahuasca and oo-koo-he, which were the subjects of his master's thesis.
In Brazil, a number of modern religious movements based on the use of ayahuasca have emerged, the most famous of them being Santo Daime and the Uniao do Vegetal (or UDV), usually in an animistic context that may be shamanistic or, more often (as with Santo Daime and the UDV), integrated with Christianity.  Both Santo Daime and Uniao do Vegetal now have members and churches throughout the world.
Similarly, the US and Europe have started to see new religious groups develop in relation to increased ayahuasca use. PaDeva, an American Wiccan group, has become the first incorporated legal church which holds the use of ayahuasca central to their beliefs.
Several notable celebrities have publicly discussed their use of ayahuasca, including Sting, Tori Amos, and Paul Simon (who wrote the song Spirit Voices about his experience with the brew in the Amazon).
Some Westerners have teamed up with shamans in the Amazon rainforest regions, forming Ayahuasca healing retreats that claim to be able to cure mental and physical illness and allow communication with the spirit world. Though both anecdotal reports and scientific studies affirm that ritualized use of ayahuasca may improve mental and physical health, the monoamine oxidase inhibitor (MAOI) component of the brew is a powerful compound that interacts with many foods that some Westerners would not consider dangerous, from liver to Vegemite.  Therefore, observing strict dietary restrictions is required before taking ayahuasca.

## "Ayahuasca tourism"
"Ayahuasca tourists" is a slighting term for those who quest for a transcendent experience through using ayahuasca and usually implies insincere Westerners who want a taste of an exotic ritual. Not all Westerners who have teamed up with Amazonian shamans are considered "ayahuasca tourists", or provide modified services directed specifically to Westerners. Genuine pilgrims from Colombia, Argentina, or Mexico also come for ayahuasca healing.
People such as these include many explorers of consciousness, writers, researchers, medical doctors, journalists, amateur anthropologists and ethno botanists, alongside vision quest seekers, and knowledge seekers who take part in ayahuasca retreats. The retreats offer the encounter with ayahuasca as an opportunity to re-balance and re-centre their lives, to clear emotional blocks, in a way that has to do with healing and personal evolution.

## Initiation
Usually a visitor who wishes to becomes a "dietero" or "dietera" that is, a male or female apprentice-shaman learning the way of the teacher plants undergoes a rigorous initiation. This can involve spending a year in the jungle. This initiation challenges and trains the initiate through extreme circumstances covering isolation, deprivation from utilities available in civilization and its conveniences, enduring radical weather of heavy rains, storms, intense heat, insects and solitude.

# Modern descriptions
Wade Davis (author of The Serpent and The Rainbow) describes the traditional mixture as tough in his book One River: "The smell and acrid taste was that of the entire jungle ground up and mixed with bile." 
Writer Kira Salak describes her personal experiences with ayahuasca in the March 2006 issue of  magazine. The article includes a candid description of how ayahuasca cured her depression, as well as provides detailed information about the brew. Here is an excerpt from the article about Dr. Charles Grob's landmark findings:
The taking of ayahuasca has been associated with a long list of documented cures: the disappearance of everything from metastasized colorectal cancer to cocaine addiction, even after just a ceremony or two. It has been medically proven to be nonaddictive and safe to ingest. Yet Western scientists have all but ignored it for decades, reluctant to risk their careers by researching a substance containing the outlawed DMT. Only in the past decade, and then only by a handful of researchers, has ayahuasca begun to be studied. At the vanguard of this research is Charles Grob, M.D., a professor of psychiatry and pediatrics at UCLAs School of Medicine.
In 1993 Dr. Grob launched the Hoasca Project, the first in-depth study of the physical and psychological effects of ayahuasca on humans. His team went to Brazil, where the plant mixture can be taken legally, to study members of a church, the Uniao do Vegetal (UDV), who use ayahuasca as a sacrament, and compared them to a control group that had never ingested the substance. The studies found that all the ayahuasca-using UDV members had experienced remission without recurrence of their addictions, depression, or anxiety disorders. Unlike most common anti-depressants, which Grob says can create such high levels of serotonin that cells may actually compensate by losing many of their serotonin receptors, the Hoasca Project showed that ayahuasca strongly enhances the bodys ability to absorb the serotonin thats naturally there. 'Ayahuasca is perhaps a far more sophisticated and effective way to treat depression than SSRIs ,' Grob concludes, adding that the use of SSRIs is 'a rather crude way' of doing it. And ayahuasca, he insists, has great potential as a long-term solution.

# Plant constituents

## Traditional
Traditional Ayahuasca brews are always made with Banisteriopsis caapi as an MAOI, although DMT sources and other admixtures vary from region to region.  There are several varieties of caapi, often known as different "colors", with varying effects, potencies, and uses.
DMT admixtures:
- Psychotria viridis (Chakruna) - leaves
- Diplopterys cabrerana (Chaliponga, Banisteriopsis rusbyana) - leaves
- Psychotria carthagensis (Amyruca) - leaves
Other common admixtures:
- Justicia pectoralis
- Brugmansia (Toe)
- Nicotiana rustica (Mapacho, variety of tobacco)
- Ilex guayusa, a relative of yerba mate

## Western Ayahuasca analogs
Although traditional plant materials are often used, sources with similar chemical constituents are often substituted for the traditional ingredients.
MAOI:
- Harmal (Peganum harmala, Syrian Rue) - seeds
- Passion flower
- medicinal MAOIs
DMT admixture sources:
- Acacia maidenii (Maiden's Wattle), Acacia phlebophylla, and other Acacias, most commonly employed in Australia - bark
- Anadenanthera peregrina, A. colubrina, A. excelsa, A. macrocarpa
- Mimosa hostilis (Jurema) - root bark - not traditionally employed with ayahuasca by any existing cultures, though likely it was in the past. Popular in Europe and North America.

# Legal status
Internationally, DMT is a Schedule I drug under the Convention on Psychotropic Substances. The Commentary on the Convention on Psychotropic Substances notes, however, that the plant itself is excluded from international control:
A fax from the Secretary of the International Narcotics Control Board to the Netherlands Ministry of Public Health sent in 2001 goes on to state that "Consequently, preparations (e.g.decoctions) made of these plants, including ayahuasca, are not under international control and, therefore, not subject to any of the articles of the 1971 Convention." 
The legal status of these plants in the United States is somewhat questionable.  Ayahuasca plants and preparations are legal as they contain no scheduled chemicals. However, brews made using DMT containing plants are illegal since DMT is a Schedule I drug.  That said, some people are challenging this, using arguments similar to those used by peyotist religious sects, such as the Native American Church. A court case allowing Uniao do Vegetal to use the tea for religious purposes in the United States, Gonzales v. O Centro Espirita Beneficente Uniao do Vegetal, was heard by the U.S. Supreme Court on November 1, 2005; the decision, released February 21, 2006, allows the UDV to use the tea in its ceremonies pursuant to the Religious Freedom Restoration Act.
Religious use in Brazil was legalized after two official inquiries into the tea in the mid-1980s, which concluded that ayahuasca is not a recreational drug and has valid spiritual uses.  (More on the legal status of ayahuasca can be found in the Erowid vault on the legality of ayahuasca.)
In France, Santo Daime won a court case allowing them to use the tea in early 2005; however, they were not allowed an exception for religious purposes, but rather for the simple reason that they did not perform chemical extractions to end up with pure DMT and harmala and the plants used were not scheduled.  Four months after the court victory, the common ingredients of Ayahuasca as well as harmala were declared stupefiants, or narcotic schedule I substances, making the tea and its ingredients illegal to use or possess. See  and  Template:Fr icon for more information.