Oral Esketamine as Alternative for Maintenance Electroconvulsive Therapy in Patients With Treatment-Resistant Depression

Objectives This study investigates repeated oral esketamine as a substitution strategy for maintenance electroconvulsive therapy (M-ECT) in eight patients with treatment-resistant depression (TRD). Methods In a 6-week dosing phase, esketamine was titrated from 0.5 or 1.0 mg/kg to a maximum of 3.0 mg/kg twice weekly. Outcomes included 6-week change in Inventory of Depressive Symptomatology — Self-rated (IDS-SR), Hamilton Depression Rating Scale — 17 items (HDRS 17 ), and Outcome Questionnaire 45 (OQ-45), along with esketamine treatmentcontinuation. Results Depression severity remained stable or improved in five patients, whereas three experienced worsening symptoms and resumed M-ECT. OQ-45 scores were available for five patients, all of whom showed improvement. Currently, four patients are still receiving oral esketamine. Conclusions Repeated oral esketamine may be a suitable and patient-friendly alternative to M-ECT. We recommend controlled trials to compare long-term safety and efficacy.