When I use a word . . . Terminology of hallucinogenic agents

Many terms have been invented to describe different types of hallucinogenic drugs, sometimes based on an analogy with the symptoms of schizophrenia, such as “psychotomimetic” and “phrenotropic.” “Psychedelics” refers to drugs that act as agonists at serotonin 5-HT_2A receptors in the brain; they include psilocybin, 5-methoxydimethyltryptamine, and N,N-dimethyltryptamine (tryptamine derivatives), mescaline (a phenethylamine derivative), and lysergic acid diethylamide (LSD, a lysergamide). “Entactogens” refers to drugs that are supposed to touch you within your mind; they act by increasing release of 5-hydroxytryptamine from presynaptic serotonergic neurons and include amfetamine, methylenedioxymetamfetamine (ecstasy, E, MDMA), 5-methoxy-2-aminoindane, and the cathinones methylone and 3-methylmethcathinone. “Oneirogens” refers to drugs that induce a dream-like state similar to the oneirophrenia that is sometimes seen in schizophrenia; they include ibogaine and harmaline alkaloids. “Entheogens” refers to drugs that are used in religious rituals or to elicit a spiritual experience; they include peyote and psilocybin. However, despite the introduction of these and other terms to describe all kinds of hallucinogenic or mind-altering substances, we still don’t understand the pathophysiology of schizophrenia.