Combined use of clozapine and ECT: a review

This paper aims to review the available evidence for the use of clozapine and electroconvulsive therapy (ECT) in combination.

Electronic searches were carried out to identify reports describing the combined use of clozapine and ECT.

Forty reports including 208 patients were identified. The majority of reports were in the form of case reports and case series, with few retrospective and open-label studies. The majority of patients were aged between 18 and 65 years and diagnosed with schizophrenia or schizoaffective disorder. Most of the patients refractory to clozapine were started on ECT as an augmentation therapy; however, in some reports, both ECT and clozapine were started concurrently, and in few cases clozapine was started after ECT. In terms of effectiveness, 37.5-100% patients improved in short-term, and sustained long-term improvement (3 weeks to 24 months) was described in few studies. In terms of the side-effect profile, five patients each had delirium and tachycardia and only four patients were described to have prolonged seizures. Overall, the combination was considered effective and safe.

There is evidence for the effectiveness and safety of the clozapine-ECT combination and it should be used in patients with treatment-resistant schizophrenia who do not respond to clozapine.