Lysergic acid diethylamide
Lysergic acid diethylamide, abbreviated
LSD or
LSD-25, also known as
lysergide and colloquially as
acid, is a semisynthetic psychedelic drug of the ergoline family, well known for its psychological effects which can include altered thinking processes, closed- and open-eye visuals, synesthesia, an altered sense of time and spiritual experiences, as well as for its key role in 1960s counterculture. It is used mainly as an entheogen, recreational drug, and as an agent in psychedelic therapy. LSD is non-addictive, is not known to cause brain damage, and has extremely low toxicity relative to dose. However, acute adverse psychiatric reactions such as anxiety, paranoia, and delusions are possible. LSD was first synthesized by Albert Hofmann in 1938 from ergotamine, a chemical derived by Arthur Stoll from ergot, a grain fungus that typically grows on rye. The short form "LSD" comes from its early code name
LSD-25, which is an abbreviation for the German "Lysergsäure-diethylamid" followed by a sequential number.