PERSONALITY FACTORS IN VARIABILITY OF RESPONSE TO PHENOTHIAZINES

Chiorpromazine, while a drug of proven efficacy in clinical psychiatry, does nonetheless, “backfire” on occasions. Rather than reducing a patient’s anxiety or producing a calming effect, the patients may exhibit increased agitation, paranoid reactions, or heightened anxiety after its administration. This variability of response has been attributed by both clinicians and researchers to differences in the personality structure of the drug recipient. In one of our early studies( 1), we had examined the effects of a number of drugs in normal male volunteers. Clear patterns of action emerged for each drug, but considerable variability of response to each was also noted. In a post hoc analysis of data, we found that our student volunteers could be separated into two contrasting personality types. The first group, which we called Type A’s, were extroverted athletes with a low anxiety level, while the other group, Type B’s, were introverted intellectuals with a high anxiety level. Members of each type showed a distinctly different response to reserpine, phenyltoloxamine, and a placebo. From an examination of the psychodynamics of the two personality types, we inferred that a major factor underlying the variability of response to phenyltoloxamine was the differential meaning that the subjects ascribed to its sedative-hypnotic actions. The subjects in turn reacted differently depending on the meaning of the sedative-hypnotic effects to them. Recently we investigated the psychophysiologic effects of a number of pheno