A double-blind, randomized controlled trial of duloxetine for pain in Parkinson's disease.

BACKGROUND:

Duloxetine proved effective for treating pain in people with Parkinson's disease in a single-arm, open-label study.

OBJECTIVE:

To evaluate the efficacy of duloxetine in a double-blind, randomized, placebo-controlled trial.

METHODS:

We randomly assigned 46 patients with Parkinson's disease with pain to either the duloxetine 40 mg/day arm or the placebo arm. After 10 weeks, we tested the change from baseline in 24-hour average pain severity measured by a visual analogue scale.

RESULTS:

We could not confirm the effect of duloxetine on pain. Exploratory analyses indicated that treatment with duloxetine was associated with improved scores on the Unified Parkinson's Disease Rating Scale Part III and 3 domains of the Parkinson's Disease Questionnaire - 39.

CONCLUSIONS:

The study failed to provide evidence for the use of duloxetine for treating pain in people with Parkinson's disease.