Continuous Subcutaneous Apomorphine as a Temporary Bridging Therapy for Dopamine Dysregulation Syndrome in Patients with Deep Brain Stimulation

BACKGROUND: Dopamine dysregulation syndrome (DDS) is a challenging complication of dopaminergic therapy in Parkinson's disease and can persist despite subthalamic deep brain stimulation (STN-DBS). We evaluated a temporary bridging concept in which oral dopaminergic medication was replaced by continuous subcutaneous apomorphine infusion while maintaining DBS. CASES: Six patients with STN-DBS and DDS were temporarily transitioned from oral dopaminergic medication to continuous subcutaneous apomorphine infusion. Treatment success was defined as reduction of DDS below a predefined threshold (<3 characteristic DDS features). Four of six patients (66.7%) no longer fulfilled the operational DDS criteria. Typical apomorphine-related adverse effects occurred in all patients; however, nausea and malaise limited the treatment in two non-responders. CONCLUSIONS: In this uncontrolled case series, continuous subcutaneous apomorphine may represent a useful temporary adjunct to STN-DBS for managing DDS in selected patients. Treatment tolerability appears to be a major determinant of success and requires careful patient selection and monitoring.