Studies on Lysergic Acid Diethylamide (LSD-25)

Abstract

The striking mental changes induced by the diethylamide of lysergic acid (hereafter referred to as LSD) have been studied extensively in Europe,* Great Britain,† and the United States.‡ In minute doses (20γ to 120γ) LSD induces a peculiar mental state characterized by anxiety, signs of autonomic dysfunction, perceptual distortion (chiefly visual), alterations in mood and affect, synesthesias, feelings of depersonalization, and hallucinations. The drug is apparently the most effective and safest agent for inducing an experimental, but reversible, psychosis in nonpsychotic subjects. Various interpretations have been placed on the mental state produced by LSD. Some European authors refer to it as a "toxic psychosis of the exogenous reaction type" or a "diencephalosis,"§ presumably because the autonomic signs suggest effects on the hypothalamus. The resemblance of some of the psychic manifestations which follow LSD to symptoms of the major psychoses has been stressed by others.∥ The LSD reaction has been referred