Abstract

The Minnesota Multiphasic Personality Inventory (MMPI) was administered to 66 non-narcotic drug abusers as part of an intensive study of polydrug abuse. Patients were classified into four primary drug-of-abuse groups using either stimulants, barbiturates, other sedative-hypnotics, or a combination of these drugs. It was readministered to 42 of these patients after 2 weeks' hospitalization. At admission, the group's MMPI profile was consistent with psychosis. At discharge, most of the MMPI T-scores were sharply reduced, and the groups' profile was consistent with sociopathy. The admission MMPI profiles of the four primary drug-of-abuse groups did not differ. At discharge, the stimulant group's profile remained psychotic, while the profiles of the other three groups were not psychotic. Such results raise the possibility of a toxic psychotic effect of chronic non-narcotic drug abuse. The group of stimulant abusers appeared schizophrenic, while the other groups of non-narcotic drug abusers appeared sociopathic.