In two studies, the relationship among depressive symptoms, depression, and psychotropic drugs was examined. In the first study, imipramine hydrochloride was administered in low and high dosages to chronic schizophrenic patients with prominent apathy and anergy, viz, symptoms of depression. Stimulating properties (improvement in areas of motor retardation and emotional withdrawal, worsening in tension) were noted. Not all patients displayed signs of stimulation; no suppression of the stimulative effect occurred with high dosages. The hypothesis that thiothixene might have a stimulative effect at low dosages in the above patients was not supported.
In the second study, thiothixene was compared with amitriptyline hydrochloride in the treatment of 40 patients who had been diagnosed as suffering from endogenous depression. Global ratings and rating scales favored amitriptyline. These results suggest that antidepressants are the treatment of choice in the diagnosis of depression, but they are probably contraindicated in symptoms of depression.