Methylphenidate improves fatigue scores in Parkinson disease: a randomized controlled trial.

Fatigue is a common nonmotor symptom in idiopathic Parkinson disease (IPD) that can prominently affect everyday function. This study was a randomized, double-blind, placebo-controlled trial evaluating methylphenidate for the treatment of fatigue in patients with IPD maintained on their regular medications. Thirty-six patients were randomized to receive either methylphenidate (10 mg three times per day; n = 17) or placebo (n = 19) for 6 weeks. Primary outcomes were the change from baseline on two separate self-report fatigue questionnaires: the Fatigue Severity Scale (FSS) and the Multidimensional Fatigue Inventory (MFI). Secondary outcomes included the Unified Parkinson Disease Rating Scale (UPDRS) motor score and the five individual domains of the MFI. Fourteen patients in the methylphenidate group and 16 patients in the control group remained on the intervention for the entire study period. In the treatment arm, mean FSS score was reduced by 6.5 points (from a baseline of 43.8) and mean MFI score was reduced by 8.4 points (from a baseline of 51.0). Both these reductions were significant (P < 0.04). Smaller reductions in the placebo group were nonsignificant. Mean UPDRS motor score did not change significantly in either group. Analysis of MFI subscores showed a significant reduction in General Fatigue in the methylphenidate group (P < 0.001). Overall, adverse effects of medication were more frequent in the placebo group. In conclusion, methylphenidate was effective in lowering fatigue scores in patients with IPD following a 6-week treatment period.