Study objectives: To determine whether pramipexole used over an extended time for restless legs syndrome (RLS) remains effective; whether the dose of the drug needs to be increased; whether augmentation develops; and whether side effects, especially sleepiness, are prominent.
Design: Retrospective review of the records of consecutive patients treated with pramipexole for RLS.
Setting: Sleep disorders center in an academic hospital.
Patients: 60 consecutive patients treated with pramipexole for RLS.
Measurements and results: Pramipexole was completely effective in controlling RLS in 67%, partially effective in 27%, and ineffective in 7% of patients. Eleven patients (18%) discontinued pramipexole after less than 4 months; the remainder were followed for a mean of 27.2 months, during which only 4 others stopped the drug. The median daily dose increased from 0.38 mg after stabilization to 0.63 mg at the end of the study. Forty percent experienced mild side effects, most commonly insomnia, nausea or dyspepsia, and dizziness. Only 5% experienced sleepiness, and none experienced sleep attacks while driving. Augmentation developed in 33%, most in the first year and all by 30 months. Augmentation was not predictable by prior augmentation with other dopaminergic agents. Only 1 patient discontinued pramipexole because of augmentation.
Conclusions: Pramipexole was effective for RLS with continued response with time. Modest escalations in dose occurred, partly due to additional doses prescribed for augmentation. Side effects were common, but generally mild and tolerated. Sleepiness while driving was not a problem. Augmentation occurred in 33% of patients but was treatable with increased doses earlier in the day.