To measure the change of mental status, medication dosage, and adverse effect of medication in patients with treatment refractory schizophrenia after administering ECT.

To objectively demonstrate the change of pharmacological response in patients with treatment refractory schizophrenia after receiving ECT.

A retrospective study of seventeen patients was done. All patients were diagnosed with schizophrenia and received ECT as secondary indications in a psychiatric hospital in Japan from 2004 to 2010. As part of the evaluation protocol, Clinical Global Impression (CGI) scale was administered at the baseline and twelve months after taking ECT. The dosages of antipsychotics were also evaluated as Chlorpromazine (CPZ) equivalents.

On twelve months, nine patients were able to maintain their improvement with pharmacological treatment only. On the contrary, eight patients failed to pharmacological treatment and were rehospitalized. Five of them required additional course of ECT. Two patients continued to take maintenance ECT. Mean CPZ equivalents were reduced from 1,505 mg to 1,130 mg.

ECT may revitalize the pharmacological response to antipsychotic medications even if the same medication failed to gain satisfactory improvement before. ECT may also reduce the dosage of antipsychotics required to avoid relapse although the change of dosage was small. We need large samples and further studies to determine the clinical significance of these findings.