Azacyclonol (aka gamma-pipradrol) is an ataractive agent; a compound which diminished hallucinations in psychotic individuals. It is sometimes referred to as a tranquilizer or antipsychotic, though it does not actually possess these properties. It was used in Europe during the 1950's for treatment of schizophrenia; likely to reduce the psychedelic effects of LSD and mescaline. However, it had mixed clinical effectiveness and did not gain widespread adoption and was eventually discontinued. Azacyclonol was sold under several trade names: Ataractan, Calmeran, Frenoton, Frenquel and Psychosan.