mescaline, perception-altering substance found in peyote. See hallucinogenic drug.

Hallucinogen, the active principle in the flowering heads of the peyote cactus. An alkaloid related to epinephrine and norepinephrine and first isolated in 1896, mescaline is usually extracted from the peyote and purified, but can also be synthesized. When it is taken as a drug, its hallucinogenic effects begin in two to three hours and may last over 12 hours; the hallucinations vary greatly among individuals and from one time to the next, but they are usually visual rather than auditory. Side effects include nausea and vomiting.

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Mescaline or 3,4,5-trimethoxyphenethylamine is a naturally-occurring psychedelic alkaloid of the phenethylamine class. It is mainly used as a recreational drug, an entheogen, and a tool to supplement various practices for transcendence, including in meditation, psychonautics, art projects, and psychedelic psychotherapy.

It occurs naturally in the peyote cactus (Lophophora williamsii), the San Pedro cactus (Echinopsis pachanoi) and the Peruvian Torch cactus (Echinopsis peruviana), and in a number of other members of the Cactaceae. It is also found in small amounts in certain members of the Fabaceae (bean family), including Acacia berlandieri. Mescaline was first isolated and identified in 1897 by the German Arthur Heffter and first synthesized in 1919 by Ernst Späth.

History and usage

The use of peyote in Native American religious ceremonies has been noted since the earliest European contact, notably by the Huichols in Mexico, but other cacti such as the San Pedro have been used in different regions, from Peru to Ecuador.

Aldous Huxley experimented with the use of mescaline. So did Aleister Crowley as reported in his diary, as well as the famous sex psychologist Havelock Ellis.By coincidence or experimentation, mescaline may have played a part in the development of the Cubist school of abstract art. When George Braque and Pablo Picasso published the "Cubist Manifesto" they described design paradigms which were similar to visual experiences induced by mescaline.

In traditional peyote preparations the top of the cactus is cut at ground level, leaving the large tap roots to grow new 'Heads'. These 'Heads' are then dried to make disk-shaped buttons. Buttons are chewed to produce the effects or soaked in water for an intoxicating drink. However, the taste of the cactus is bitter, so users will often grind it into a powder and fill them in capsules to avoid having to taste it. The effective human dosage is 300–500 milligrams of pure mescaline. Hallucinations occur at 300–600mg, which is the equivalent to approximately 9-20 small peyote buttons. The average 3 inch button contains about 25mg mescaline.

Pharmacokinetics

Although the ED₅₀ is variable with dosage and individual, the LD₅₀ has been measured in various animals and is reported as follows:

• 212 mg/kg i.p. (mice)
• 132 mg/kg i.p. (rats)
• 328 mg/kg i.p. (guinea pigs)

It is reported that mescaline is 1000-3000 times less potent than LSD, and 30 times less potent than psilocybin. About half the initial dosage is excreted after 6 hours, but some studies suggest that it is not metabolized at all before excretion.

Tolerance builds with repeated usage, and it is suggested that a cross-tolerance can be developed with LSD and psilocin.

Mescaline appears to not be subject to metabolism by CYP2D6 and between 20 and 50% of mescaline is excreted in the urine unchanged, and the rest being excreted as the carboxylic acid form of mescaline, a likely result of MAO degradation.

Behavioral and non-behavioral effects

Hallucinations produced by mescaline are somewhat different from those of LSD. Hallucinations are consistent with actual experience, but are typically intensifications of the stimulus properties of objects and sounds. Prominence of color is distinctive, appearing brilliant and intense. Placing a strobing light in front of closed eyelids can produce brilliant visual effects at the peak of the experience. Recurring visual patterns observed during the mescaline experience include stripes, checkerboards, angular spikes, multicolored dots, and other very simple fractals which turn very complex. Aldous Huxley described these self transforming amorphous shapes as like animated stained glass illuminated from light coming through the eyelids. Like LSD, mescaline induces distortions of form and kaleidoscopic experiences but which manifest more clearly with eyes closed and under low lighting conditions however all of these visual descriptions are purely subjective. And like with LSD, synesthesia can occur especially with the help of music.An unusual but unique characteristic of mescaline use is the "geometricization" of three-dimensional objects. The object can appear flattened and distorted, similar to the presentation of a Cubist painting.

Mescaline elicits a pattern of sympathetic arousal, with the peripheral nervous system being a major target for this drug.

Effects last for up to 12 hours.

Mode of action

Mescaline acts similarly to other psychedelic agents . Mescaline binds to, and activates the serotonin 5-HT_2A receptor with a high nanomolar affinity . How activating the 5-HT2A receptor leads to hallucinations is still unknown, but it likely somehow involves exciting cortical neurons.

Legal status

In the US it was made illegal in 1970 by the Comprehensive Drug Abuse Prevention and Control Act. It was prohibited internationally by the 1971 Convention on Psychotropic Substances and is categorized as a Schedule I hallucinogen by the CSA. Mescaline is only legal for certain natives (such as those involved in the Native American Church). Penalties for manufacture or sale can be as high as five years in prison and a fine of $15,000, with a penalty of up to one year and fine of $5000 for possession. In the UK, mescaline is a Class A drug (in powder form, although dried cactus can be bought and sold legally, unlike raw "magic" mushrooms, which are now illegal), and so carries the following penalties. For possession: up to seven years in prison or an unlimited fine or both. For dealing: up to life in prison or an unlimited fine or both.

Analogs

Mescaline has a number of analogs, featuring the methoxy groups altered to include thio groups or to be extended. Examples include, but are not limited to, isomescaline, thiomescaline, escaline, thioescaline, proscaline, isoproscaline, buscaline, thiobuscaline, thioisomescaline, phenescaline, symbescaline, asymbescaline, thioasymbescaline, allylescaline, methallylescaline, metaescaline, and thiometaescaline. It has an active amphetamine homolog, 3,4,5-trimethoxyamphetamine.

See also

• The Doors of Perception
• Project MKULTRA
• PiHKAL
• Psychoactive drug

References

Notes

External links

• Mescaline at Erowid
• PiHKAL entry
• Mescaline: The Chemistry and Pharmacology of its Analogs, an essay by Alexander Shulgin
• Mescaline on the Mexican Border