Maintenance Electroconvulsive Therapy Emphasizing Relapse Prevention in Parkinsonian Syndromes With Psychiatric Comorbidities.

Parkinsonian syndromes with comorbid psychiatric illness present a therapeutic paradox wherein antipsychotics may worsen motor symptoms while dopaminergic agents may exacerbate psychosis. Maintenance electroconvulsive therapy (mECT) has emerged as a critical relapse-prevention strategy, reducing 6-month relapse risk by 43% compared to pharmacotherapy alone. We present 2 cases demonstrating mECT efficacy in sustaining both psychiatric and motor improvements. First, a 70-year-old woman with Parkinson's disease and treatment-resistant schizophrenia improved after acute ECT; motor symptoms relapsed 2 months post-discontinuation but recovered with mECT, allowing medication de-escalation without cognitive decline. Next, a 47-year-old man with multiple system atrophy and severe depression with psychosis showed marked improvement after acute ECT; motor relapse at 1 month was prevented by mECT. Both cases demonstrate that motor improvement cannot be sustained without continued ECT intervention. mECT represents an underutilized strategy deserving wider adoption in neurodegenerative-psychiatric comorbidity, warranting larger prospective trials to establish standardized protocols.