The Antiaggressive Action of Combined Haloperidol-Propranolol Treatment in Schizophrenia

Psychopharmacological interventions for managing aggression in schizophrenia have thus far yielded inconsistent results. This study evaluates the antiaggressive efficacy of combined haloperidol-propranolol treatment. Thirty-four newly admitted schizophrenic patients were studied in a controlled double-blind trial. Following a 3-day drug-free period and 7 days of haloperidol treatment, patients were randomly assigned to receive either haloperidol-propranolol or haloperidol-placebo for eight consecutive weeks. Doses of medications were adjusted as necessary; biperiden was administered if required. Rating scales were applied to assess aggression, anger, psychosis, depression, anxiety and extrapyramidal symptoms. The mean daily dose of haloperidol was 21 mg (SD = 6.4) in the research group and 29 mg (SD = 6.9) in the controls. Mean and maximal daily doses of propranolol were 159 mg (SD = 61) and 192 mg (SD = 83), and of placebo, 145 mg (SD = 50) and 180 mg (SD = 70), respectively. Compared with the controls, the scores for the research patients decreased significantly from baseline, particularly after 4 weeks of treatment, for some dimensions of anger, psychosis, anxiety, and neuroleptic-induced parkinsonism. A tendency for reduced aggression was shown in the combined haloperidol-propranolol group for some dimensions but not others. These patients also required significantly less biperiden. The tendency toward elevated antiaggressive effect of combined haloperidol-propranolol treatment compared to haloperidol alone may be explained by a simultaneous decrease in aggression, psychotic symptomatology, and anxiety.