LSD

LSD, or lysergic acid diethylamide, hallucinogenic drug that induces a state of excitation of the central nervous system and overactivity of the autonomic nervous system, manifested as changes in mood (usually euphoric, sometimes depressive) and perception. LSD was invented in 1938 by 2 Swiss chemists, Arthur Stoll and Albert Hofmann. No evidence of physical dependence can be detected when the drug is abruptly withdrawn. A high degree of tolerance develops and disappears rapidly. The chief danger to the individual is the psychological effect and impairment of judgment, which can lead to dangerous decisionmaking or accidents.

Responses to LSD depend on several factors, including the individual's expectations, the setting, and his or her ability to cope with perceptual distortions. Untoward reactions to LSD apparently have become rare, but adverse reactions appear as anxiety attacks, extreme apprehensiveness, or panic states. Most often these reactions quickly subside with appropriate management in a secure setting. However, some individuals remain disturbed and may even show a persistent psychotic state. It is unclear whether the drug use has precipitated or uncovered a pre-existing psychotic potential or whether this can occur in previously stable individuals.

Some persons, especially those who are chronic or repeated users, may experience drug effects after they have discontinued use of the drug. Referred to as “flashbacks,” these episodes most commonly consist of visual distortions, but can include distorted perceptions of time, space, or selfimage. Such episodes may be precipitated by the use of marijuana, alcohol, or barbiturates or by stress or fatigue, or they may occur without apparent reason. The mechanisms that produce flashbacks are not known, but they tend to subside over a period of 6 months to 1 year.

See also: Drug; Drug abuse.