Response to drugs in schizophrenia: the influence of family history, obstetric complications and ventricular enlargement.

A prospective study of antipsychotic drug treatment showed no difference in response between schizophrenic in-patients with or without a familial predisposition to the illness (N = 53). All patients received at least 600 mg chlorpromazine equivalents antipsychotic medication for 6 weeks. Ventricle brain ratios, ratings of cortical sulcal widening and a history of obstetric complications also failed to account for the variability, but early age of onset was associated with unsatisfactory response.