Orally Disintegrating Selegiline in Parkinson Patients with Dopamine Agonist-related Adverse Effects

Objective: To determine whether adding orally disintegrating selegiline (ODS) while decreasing dopamine agonist (DA) dosages would reduce DA-related adverse effects (AEs) of excessive daytime sleepiness (EDS), pedal edema, hallucinations, and impulse control disorders (ICDs) without compromising efficacy in Parkinson disease (PD) patients.

Methods: This was a 12-week open-label study of 60 PD patients with motor fluctuations and DA-related AEs of EDS, pedal edema, hallucinations, and ICDs. Orally disintegrating selegiline was initiated at 1.25 mg once daily, and down titration of the DA was started with a goal of a 50% reduction by 1 week. At week 6, ODS was increased to 2.5 mg, and further reductions of the DA were allowed if the AEs were not resolved.

Results: The addition of ODS allowed a reduction in the mean daily dose of pramipexole from 2.3 to 0.5 mg and immediate-release ropinirole from 11.2 to 2.9 mg. Most subjects reported a reduction or resolution of DA-related AEs; 94% with EDS (n = 50), 73% with pedal edema (n = 26), 86% with hallucinations (n = 15), and 84% with ICDs (n = 25). Mean activities of daily living and motor scores from the Unified Parkinson's Disease Rating Scale as well as quality-of-life scores were significantly improved without an increase in daily "off" time. The most common AEs, most of which resolved after titration, were worsening of PD, nausea/vomiting, dyskinesia, increased off time, body aches, insomnia, orthostatic hypotension, and increased anxiety and depression.

Conclusions: In most subjects, the addition of ODS with decreasing dosages of DAs substantially reduced EDS, pedal edema, hallucinations, and ICDs without compromising efficacy.