PSYCHOACTIVE DRUGS FROM PLANTS


OUTLINE:
Reading

CHAPTER 12, pp. 286 ff

Introduction
A list of commonly known pyschoactive drug plants is given on page 287. A table giving the psychological classification of major plant-derived psychoactive drugs is given on page 287. Many plant derived compounds can alter one's perception of reality. They may produce feelings of tranquility, invigoration, or "other worldliness". People may use these substances to escape from reality. Many of these same compounds are used medicinally. Many are quite toxic. Sometimes the toxicity and hallucinogenic properties are interrelated or confused.
Most of the known psychoactive compounds contain nitrogen and many are alkaloids. The best known exception is the active ingredient of marijuana.
The psychoactive compounds are absorbed into the blood stream and transported to various sites where they exert their effects. They may be taken orally, injected, or absorbed through mucous membranes as in the mouth or nose. Many are absorbed through the lungs. Often, the liver is involved in degradation of the compounds.
When they reach the central nervous system, psychoactive drugs usually act by altering the natural interactions between neurons. The neurons send information by chemical messages. The chemical substances involved are called neurotransmitters. They cross the spaces to the adjacent neurons; the spaces are called synapses. Specific sites on the adjacent site bind with the neurotransmitter and this interaction triggers a response in the neuron. Among the things involved are perception of pain, emotion, interpretation of audio and visual stimuli.
Most pyschoactive drugs alter or mimic the behavior of four kinds of natural neurotransmitters: acetylcholine, norepinephrine, serotonin, and neuropeptides. Several additional modes of action are possible and the action of some (such as THC) is still not understood.
In most "primitive" cultures, use of these materials is within a cultural, religious, or medical context and they are generally not used recreationally. This context generally is lacking in our present day culture in this country. Schultes defines hallucinogens as "chemicals that produce, in non-toxic doses, changes in perception, in thought, and in mood, but which seldom produce mental confusion, memory loss, or disorientation for person, place and time".
Many synthetic ones are also known, e.g., LSD and heroin.

Marijuana
The resinous monoterpenes of Cannabis sativa(Cannabaceae) have been used in China for thousands of years. Cannabis is probably native to central Asia. The plant was early used from the Near East to China.
This plant is the source of fiber. Seed oils from cannabis are used in many Asian cultures. The plant has also been used medicinally and for its psychoactive properties. Diagram of plant page 293.
According to some sources, cannabis is the number one cash crop in the U.S. today; essentially all of it is grown illegally. Cannabis is found in ancient Chinese writings as well as in ancient Hindu texts from India. In India, the psychoactive properties of this plant were discovered.
It is still debated whether cannabis is hallucinogenic or not. Different cultivars were selected for fiber and drug use. Cannabis resin was originally eaten; in India that is the most common way that it is used today. Marco Polo reported the use of hashish in the East.
Smoking (anything) was developed by the American Indians and this process did not get introduced into Europe until the 1500's. By the time of the Crusades, the use of marijuana was found throughout Asia and Africa.
Cannabis was brought to the New World by the Spanish and the British in efforts to establish a fiber crop. In Illinois, this plant was introduced in W.W. I and W.W. II as a source of fiber for ropes. The plant has become naturalized and widespread in many areas of the state. Most of the wild cannabis in Illinois has little pyschoactive material in it.

Marijuana

Poppies and their products
We have already discussed poppies as medicinal plants. Poppies are widely cultivated for the seeds and for seed oil. They are also grown for both legal and illicit sources of opium. Morphine and codeine are isolated from crude opium and are widely used for medicinal purposes. Both are addictive. The acetylated derivative of morphine, heroin, is even more addictive. Heroin does not occur naturally.
Opium has been used for thousands of years as a narcotic. In 3000 B.C., Sumerian tablets describe use of the plant. Opium was used by most cultures of the Near East to relieve pain. Although often associated with China, the drug was first introduced there by Arab traders in the 7th century A.D. The drug was originally used as a treatment for diarrhea much as it is today.
In the 17th century, the Dutch introduced smoking to Formosa and people began to mix opium and tobacco as a treatment for malaria. The practice soon became popular in China. Although Chinese officials tried to ban the import of opium, first the Portugese, then the British, forced them to accept this material in trade. This was brought on because the Chinese had little interest in other European goods and the Europeans had to have something to trade for silk and spices. England established opium plantations in India to trade with China.
During the 1800's there were a series of opium wars in which the British (and later Germany, Russia, France, and the U.S.) took control of some key port cities of China in order to force the Chinese to trade with them. Hong Kong was one of these. The use of opium didn't come under control until the Communist government took over in 1949.
Opium wasn't commonly used in Europe until 1525 when Paracelsus (re-) discovered a way to dissolve it in alcohol. This medicinal preparation, paregoric, became popular. Morphine was isolated in 1803 and the purified alkaloid could be given in measured doses. Morphine is an potent analgesic and it was widely used in the Civil War. More than 45,000 soldiers returned home as addicts.

Mescal bean
The seeds of Sophora secundiflora(Fabaceae) have been used by the American Indians of the Southwestern U.S. as a hallucinogenic drug. They are also very toxic. See diagram page 308.

Mescal bean plant(Sophora secundiflora)

Khat
The leaves of Catha edulis(Celastraceae) have been used for many years in the Arabian peninsula. The leaves are chewed daily by many, and the plant is a major export of Ethiopia to Yemen and a number of nearby countries. Khat is banned in Saudi Arabia. Lime is frequently added to hydrolyse the alkaloids and convert them to the free bases. The plant is probably native to Africa?

Coca
This plant has also been discussed under medicinal plants. The leaves of Erythroxylum coca (Erythroxylaceae) have been chewed for thousands of years by Indians of Andean South America.
In this case also, the Indians add lime to the leaves before chewing them. Cocaine blocks readsorption of norepinephrine in the brain. This makes the user feel invigorated and blocks feelings of fatigue and hunger. The Spanish tried to prohibit coca until they realized that the Indians worked harder with it.
The leaf form of coca never became popular abroad. In 1860, cocaine was isolated and became popular. It became used as a local anesthetic. An extract of coca leaves became used in Coca Cola. Later the FDA made the company remove coca alkaloids from the extract. As a drug of abuse, cocaine may be sniffed, smoked or injected.

Coca

Yagé or ayahuasca
The resinous exudate of the stems of Banisteriopsisspp. is usually made into a drink known as yagé or ayahuasca. B. caapi is one of the most commonly used species. This is common in Colombia and Ecuador. The active compounds are harmine and other related alkaloids. Other plants are sometimes added as synergists, i.e., to enhance the activity.

Peyote
A number of species of cacti from the New World are known to be hallucinogenic. Among these are peyote or mescal, Lophophorawilliamsii and Trichocereus pachanoi. The former is from Mexico and the latter from the Andes of South America. Mescaline is the most common alkaloid. The Spanish also tried to suppress the use of these. Many Indians in Mexico and in South America continued use of these plants, however. The Native American Church (chartered about 1920) began use of these in religious rites much later (about 1890).

Peyote

Other hallucinogenic plants
A snuff made from the powdered pods of Anadananthera peregrina(Fabaceae or Leguminosae) (yopo) has been used by Indians of the Caribbean and of northern South America. The snuff is often mixed with lime (calcium hydroxide).
Snuffs also are made from the resin of Virolaspp. (Myristicaceae). This material has been used ceremonially in the Amazon region of South America. The active compound is dimethyltryptamine.
Another member of the same family, nutmeg (Myristica fragrans,) is also hallucinogenic, but relatively toxic. Nutmeg contains myristicin.
Heimia salicifolia(Lythraceae) is alleged to produce auditory hallucinations. The plant is a relatively common weed from Texas to Argentina.
Tabernanthe iboga(Apocynaceae) is reported to be used in Africa as a hallucinogen. In Gabon and the adjacent Congo, the plant is used in religious rites and in hunting game. There are also important medical uses for the plant. The active compounds are indole alkaloids.
In Europe and the Near East, many plants of the Solanaceae were used in a similar manner. Among these were Atropa belladonna, Hyoscyamusspp., Daturaspp. (also used by the North American Indians and some Asian peoples), and Mandragora species??.

Mandrake

Virola

Some South American Indians used Brunfelsia grandifloraand Brugmannsia species in a similar manner.

Hallucinogenic fungi
Among the best known of these are Amanita muscaria, the fly agaric. This fungus grows in the temperate zones of Europe and Asia (where it has been widely used) and North America (where it has not been). In Siberia, this fungus was used before alcohol became available. The dried mushrooms were sold and were quite expensive. Even the urine from users was recycled.


Fly agaric

This fungus is mentioned in Sanskrit writings from India. In Mexico, members of the genus Psilocybe and other related mushrooms were widespread and commonly used when the Spanish arrived. The Spanish tried to supress use of these and they went underground for a couple of centuries. They also are usually used in a curative, religious manner. These hallucinogenic fungi have been used for more than 2000 years in Mexico. About 50 years ago they were rediscovered by scientists.
Psilocybin is the active compound in many of these fungi.
Another important group of fungal hallucinogens are the ergot alkaloids that come from Claviceps species on grasses. These compounds are extremely toxic and produce many physiological changes. During the middle ages they were responsible for much human poisoning. Some of them are also hallucinogenic and are partially responsible for the bizarre actions of the victims of "St. Anthony's fire".
In Mexico, the seeds of a number of Ipomoeaand Rivea species (Convolvulaceae) were used in religious-medical applications as well. They contain the same compounds more or less. One important Mexican plant of this type was called "ololiuqui".


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Revised April 2005



© David S. Seigler, Integrative Biology 363, Plants and Their Uses, Department of Plant Biology, 265 Morrill Hall, 505 S. Goodwin Ave., University of Illinois, Urbana, Illinois 61801, USA. 217-333-7577. seigler@life.uiuc.edu.