Use of Electroconvulsive Therapy for Treatment-Resistant Schizophrenia in a Patient Unable to Tolerate Clozapine Due to Clozapine-Associated Hyponatremia: A Case Report.

Clozapine is regarded as the most effective treatment for patients with treatment-resistant schizophrenia (TRS). However, serious adverse effects such as hyponatremia may necessitate discontinuation, leaving limited therapeutic alternatives. This case report describes a middle-aged male with chronic schizophrenia who developed clinically significant hyponatremia during clozapine titration, leading to its discontinuation prior to achievement of therapeutic serum concentrations. Despite prior antipsychotic trials with haloperidol, asenapine, olanzapine, and chlorpromazine, the patient had persistent auditory hallucinations and paranoid delusions. Given the patient's clozapine intolerance and persistent psychosis, a course of bifrontal electroconvulsive therapy (ECT) was initiated three times weekly over a 24-day inpatient series. The patient demonstrated progressive reduction in auditory hallucinations and paranoid ideation throughout treatment, with resolution of hallucinations and marked improvement in paranoia by discharge. Treatment was well tolerated, with only mild transient headaches and no clinically significant cognitive adverse effects observed on serial mental status examinations. At 5 months post-ECT, he remained free from readmission and without recurrence of his positive symptoms. This case highlights the potential role of ECT as a therapeutic consideration for select patients with refractory psychosis when clozapine cannot be safely continued due to medically significant adverse effects such as hyponatremia.