EVALUATION OF PHENTERMINE AND FENFLURAMINE, ALONE AND IN COMBINATION,IN NORMAL, HEALTHY-VOLUNTEERS

Recent clinical reports indicate that combined administration of phent ermine and fenfluramine may have useful effects in the treatment of dr ug abuse. The present study was designed to evaluate the subjective an d mood-altering effects of these drugs, alone and in combination, in n ormal healthy volunteers. Seven male and five female volunteers partic ipated in an eight-session, double-blind study in which each subject r eceived each of the following drug conditions: d-amphetamine (10 and 2 0 mg), phentermine (30 mg), fenfluramine (40 and 80 mg), phentermine ( 30 mg) with fenfluramine (40 mg), phentermine (30 mg) with fenfluramin e (80 mg), and placebo. Sessions were conducted in a laboratory settin g two or three days a week. Subjects completed standardized self-repor t questionnaires and psychomotor tests before and at regular intervals after each drug administration. Phentermine produced effects that wer e similar to those of d-amphetamine, whereas fenfluramine produced dif ferent and apparently aversive effects (e.g., it increased measures of anxiety and confusion). Phentermine reduced the apparently aversive e ffects of fenfluramine when the two drugs were given together. These r esults suggest that the combination of phentermine and fenfluramine wo uld have a low potential for abuse.