Hallucinogens are a diverse group of drugs that cause an alteration in perception, thought, or mood. A rather heterogeneous group, these compounds have different chemical structures, different mechanisms of action, and different adverse effects. Despite their name, most hallucinogens do not consistently cause hallucinations, which are defined as false sensations that have no basis in reality. Often, they are more likely to cause changes in mood or in thought than actual hallucinations.
Hallucinogens share a rich history. Many cultures have used hallucinogens for religious or mystical experiences. The Hindu holy book, Rig Veda,mentions soma, a sacred substance used to induce higher levels of consciousness. Soma is thought to have been derived from the juice of the hallucinogenic mushroom Amanita muscaria as shown in the image below. The Aztecs in pre-Columbian Mexico described the ceremonial use of teotlaqualli, a paste made from the hallucinogenic flower, ololiuqui. Rubbed on the skin of Aztec priests and soldiers, it was thought to eliminate fear and place the user in a proper mental state to serve the Aztec gods. The Mexican Indians have a long history of using peyote, a mescaline-containing hallucinogen, in religious ceremonies. Hallucinogens have also been proposed as a cause of the “immoral and illicit” behavior of alleged witches in the Salem, Massachusetts witch trials.
Hallucinogens. Amanita muscaria.
The first synthetic hallucinogen, lysergic acid diethylamide (LSD) 25, was accidentally discovered in 1938 by Sandoz laboratories while searching for a new ergot-derived analeptic agent. Its discoverer, a Swiss chemist named Albert Hoffman, began to experience hallucinations after an inadvertent skin exposure to the drug. Sandoz began marketing the new drug in 1947. Delysid, as the drug was called, was used by psychiatrists who believed its use in psychotherapy could help the patient access repressed emotions. The US Central Intelligence Agency also conducted human experiments with LSD, testing its use as an interrogation tool and as a mind-control agent. Unfortunately, many of these studies were conducted without the consent or knowledge of the participant.
LSD use increased in the late 1950s and early 1960s. Popularized by the media and by people such as Timothy Leary, experimentation with psychedelics reached a peak in the mid 1960s. As use increased, adverse reactions began to be reported. In 1966, because of mounting public health concerns, the federal government banned LSD. Illicit manufacture and use of hallucinogens, of course, has continued.
