This prospective, open-label, multicentre study examined the efficacy and safety of rapidly (overnight) or slowly (after 2 weeks of concomitant usage) switching patients with Parkinson's disease (PD) from conventional ergot dopamine agonists (DAs) to the non-ergot DA, pramipexole. Fifty-nine early-to-advanced PD patients with motor symptoms that were inadequately controlled by ergot DAs were enrolled. Patients were switched from ergot derivatives to pramipexole and evaluated every 2 weeks for 12 weeks by Hoehn and Yahr staging, Unified Parkinson's Disease Rating Scale (UPDRS) and a modified Epworth Sleepiness Scale (mESS). The UPDRS III subscores and total UPDRS scores significantly improved, independent of switching method. Adverse events, all of which were mild, occurred in 29.2% of patients. No sudden onset of excessive daytime sleepiness or significant worsening in mESS was seen. Switching patients with PD from ergot DA to pramipexole, using either a slow or rapid switching method, appeared to be well tolerated and effective, although further dose adjustment may be necessary in some patients after the switch.