While many drugs speed up or depress the central nervous system, there is a class of drugs that distorts how we feel, hear, see, smell, taste, and think. Called hallucinogens because users often hallucinate, or experience nonexistent sensations, these drugs are also known as psychedelic, or mind-bending, drugs. Some hallucinogens come from natural sources; others are made in laboratories. Examples of natural hallucinogens are mescaline, psilocybin, DMT, and marijuana. Mescaline, which has been used by American Indians in religious ceremonies, comes from the peyote cactus.
Psilocybin, also used by the Indians and believed to have supernatural powers, is found in about 20 varieties of mushrooms. Once ingested, psilocybin is converted to psilocin, which is responsible for the drug’s hallucinogenic sensations. DMT (dimethyltryptamine) is a short-acting hallucinogen found in the seeds of certain West Indian and South American plants. In the form of snuff, called cohoba, it has been used in religious ceremonies in Haiti. Marijuana is a plant belonging to the hemp family .
The active principle responsible for the drug’s effects is tetrahydrocannabinol (THC), obtained from he amber-colored resin of the flowering tops and leaves of the plant. Hashish is also made from this resin. Of all drugs, synthetic and natural, the most powerful is LSD, or lysergic acid diethylamide. Twenty micrograms, an almost infinitesimal amount, is sufficient to produce a hallucinogenic effect; just 3 pounds (1. 4 kilograms) could induce a reaction in all the inhabitants of New York City and London.
This extraordinary potency makes LSD especially dangerous since it is usually impossible to determine how much is contained in doses offered by drug dealers. LSD is chemically derived from ergot, a parasitic fungus that grows on rye and other grains. An odorless, colorless, and tasteless substance, LSD is sold on the street in tablets, capsules, and sometimes liquid form. It is usually taken by mouth but can be injected. Often LSD is placed on a blotter or other absorbent paper and marked into small squares, each representing one dose.
Synthetic hallucinogens with effects resembling those of LSD include DET (diethyltryptamine), a synthetic compound similar to DMT, and DOM (2,5- dimethoxy-4-methylamphetamine), a compound that combines some of the properties f mescaline and amphetamines, as do the drugs MDA (3,4- methylenedioxyamphetamine) and MMDA (3-methoxy-3,4-methylenedioxyamphetamine). The effects of hallucinogens on the body are unpredictable. They depend on the amount taken and the user’s personality, mood, expectations, and surroundings.
Although hallucinogens do not produce a physical addiction, users do develop a tolerance, so that increasing amounts must be taken to achieve the same effect. Psychological dependence on hallucinogens is well documented. It appears that each drug carries its own risks. For example, unlike allucinogens such as LSD and synthetics such as DOM that consist of a single chemical, marijuana has been found to contain more than 400 separate substances. These substances are in turn broken down in the body into a great many more chemicals, and the effects of these chemicals on the user are poorly understood.
It has been found, however, that the most potent of these chemicals are attracted to and accumulate in fatty tissues, including the brain and reproductive organs. Studies indicate that frequent marijuana users may experience impaired short- term memory and learning ability and reproductive problems. Other studies suggest that frequent or chronic marijuana use may contribute to damage of the immune system, increased strain on the heart, delayed puberty, and chromosome damage.
The most pronounced psychological effects induced by hallucinogens are a heightened awareness of colors and patterns together with a slowed perception of time and a distorted body image. Sensations may seem to “cross over,” giving the user a sense of “hearing” colors and “seeing” sounds. Users may also slip into a dreamlike state, indifferent to the world around them and forgetful of time and lace to such an extent that they may believe it possible to step out of a window or stand in front of a speeding car without harm. Users may feel several different emotions at once or swing wildly from one emotion to another.
It is impossible to predict what kind of experience a hallucinogen may produce. Frightening or even panic-producing psychological reactions to LSD and similar drugs are common. Sometimes taking a hallucinogen will leave the user with serious mental or emotional problems, though it is unclear whether the drug simply unmasked a previously undetected disorder or actually produced it. Among the short-term physical effects of hallucinogens are dilated pupils, raised body temperature, increased heart rate and blood pressure, sweating, loss of appetite, sleeplessness, dry mouth, and tremors.
The long-term effects are less certain. LSD users may experience involuntary flashbacks during which the drug’s effects reappear without warning. Such flashbacks can occur days, months, or even years after the drug was last used. Some LSD users develop organic brain damage, manifested by impaired memory and attention span, mental confusion, and difficulty with abstract thinking. It is still unclear whether such damage can e reversed when LSD use is halted.
Although hallucinogens can pose a threat to health when used indiscriminately, they may also have therapeutic uses in medicine when administered under controlled circumstances. A synthetic form of THC, the active principle in marijuana, has been approved for prescription use by persons who suffer from the severe nausea that often accompanies cancer chemotherapy and for whom other antinausea drugs are unsuitable or ineffective. LSD was once used to treat persons with certain mental disorders, but such use was abandoned because of the drug’s harmful effects.