Lysergic acid diethylamide

Lysergic acid diethylamide, LSD, LSD-25, or acid, is a semisynthetic psychedelic drug. It is synthesized from lysergic acid derived from ergot, a grain fungus that typically grows on rye. It was first synthesized by Albert Hofmann. The short form LSD comes from its early codename LSD-25, which is an abbreviation for the German "Lysergsäure-diethylamid" followed by a sequential number.

LSD is sensitive to oxygen, ultraviolet light, and chlorine, especially in solution, though its potency may last years if it is stored away from light and moisture at low temperature. In pure form it is colorless, odorless and mildly bitter. LSD is typically delivered orally, usually on a substrate such as absorbent blotter paper, a sugar cube, or gelatin. In its liquid form, it can be administered by intramuscular or intravenous injection. The threshold dosage level for an effect on humans is of the order of 20 to 30 µg (micrograms).

Introduced by Sandoz Laboratories as a drug with various psychiatric uses, LSD quickly became a therapeutic agent that appeared to show great promise. However, the extra-medical use of the drug in Western society in the middle years of the twentieth century led to a political firestorm that resulted in the banning of the substance for medical as well as recreational and spiritual uses. Despite this, it is still considered a promising drug in some intellectual circles, and organizations such as the Beckley Foundation, MAPS, Heffter Research Institute and the Albert Hofmann Foundation exist to fund, encourage and coordinate research into its medical uses.