Naltrexone, an opiate antagonist, fails to modify motor symptoms in patients with Parkinson's disease

Mov Disord. 1994 Jul;9(4):437-40. doi: 10.1002/mds.870090410.


One month of adjunct treatment with naltrexone (100 mg/day) was compared with placebo in a double-blind, randomized, cross-over design in two groups of patients with Parkinson's disease. The first group was composed of 10 patients with a moderate motor impairment insufficiently controlled by monotherapy with bromocriptine. The second group was composed of eight patients with L-dopa-induced peak-dose dyskinesia. Naltrexone as compared with placebo did not demonstrate any significant change in motor function in either group. These negative clinical results do not support a significant role of endogenous opioid systems in the pathophysiology of motor impairment in Parkinson's disease.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial

MeSH terms

  • Aged
  • Bromocriptine / adverse effects
  • Bromocriptine / therapeutic use
  • Cross-Over Studies
  • Disability Evaluation
  • Dose-Response Relationship, Drug
  • Double-Blind Method
  • Drug Therapy, Combination
  • Dyskinesia, Drug-Induced / drug therapy
  • Female
  • Humans
  • Levodopa / adverse effects
  • Levodopa / therapeutic use
  • Male
  • Middle Aged
  • Motor Skills / drug effects*
  • Naltrexone / adverse effects
  • Naltrexone / therapeutic use*
  • Neurologic Examination / drug effects
  • Parkinson Disease / drug therapy*


  • Bromocriptine
  • Levodopa
  • Naltrexone