Combined Pimavanserin and Maintenance Electroconvulsive Therapy: A Novel Approach to Parkinson's Disease Psychosis.

Parkinson's disease (PD) is among the most common neurodegenerative diseases. Parkinson's disease psychosis (PDP) is a potential psychiatric manifestation of PD that is associated with increased morbidity and mortality. The treatment of PD with concomitant PDP is challenging as standard-of-care medication to improve motor symptoms can cause or exacerbate PDP. In this case report, we present an atypical presentation of a 70-year-old female who developed PDP only four years after her initial PD diagnosis, much earlier than the established average. Treatment was particularly complex as her PDP symptoms were refractory to PD medication reduction and oral antipsychotics, yet her PD motor symptoms were well controlled with a deep brain stimulator (DBS). We discuss a combination of pimavanserin and maintenance electroconvulsive therapy (ECT) as a safe and efficacious treatment modality which has led to remission of her PDP while DBS continues to provide adequate management of her PD symptoms. This case improves upon the early recognition of PDP and outlines a unique treatment modality not well described in the literature. This is the only case that demonstrates the efficacy of combining pimavanserin and ECT for refractory PDP in a patient with a DBS.