Does Your Patient with Schizophrenia Have Treatment Resistance or Low Plasma Drug Levels?

Treatment resistance in schizophrenia, generally defined as inadequate response to at least two adequate antipsychotic treatments, is frequent and usually calls for clozapine. To help determine true treatment resistance, investigators assessed plasma levels of antipsychotic medications in 99 consecutive consenting patients referred to a specialty clinic for treatment-resistant schizophrenia within a U.K. community mental health service (mean age, 40; 64% men; 48% black).

Of the cohort, 70% were diagnosed with schizophrenia, 20% with schizoaffective disorder, and 10% with other illnesses. Patients were prescribed oral antipsychotic monotherapy (but not clozapine); all but one patient were prescribed an atypical antipsychotic, with 49% on olan…