DrugLib.com — Drug Information Portal

Rx drug information, pharmaceutical research, clinical trials, news, and more



Effects of a dopamine agonist on the pharmacodynamics of levodopa in Parkinson disease.

Author(s): Brodsky MA, Park BS, Nutt JG

Affiliation(s): Oregon Health & Science University, 3181 SW Sam Jackson Park Rd, OP-32, Portland, OR 97239. brodskym@ohsu.edu.

Publication date & source: 2010-01, Arch Neurol., 67(1):27-32.

Publication type: Clinical Trial; Randomized Controlled Trial; Research Support, N.I.H., Extramural; Research Support, Non-U.S. Gov't

BACKGROUND: Treatment of Parkinson disease commonly includes levodopa and dopamine agonists; however, the interaction of these 2 drugs is poorly understood. OBJECTIVE: To examine the effects of a dopamine agonist on the motor response to levodopa. DESIGN: Double-blind, randomized, placebo-controlled, crossover clinical trial. SETTING: Ambulatory academic referral center. Patients Thirteen patients with idiopathic Parkinson disease taking levodopa and experiencing motor fluctuations and dyskinesia. INTERVENTIONS: Eligible individuals were randomly assigned to receive pramipexole dihydrochloride or placebo for 4 weeks followed by a 2-hour intravenous levodopa infusion on consecutive days at 2 rates and with blinded assessments. They were then crossed over to the alternate oral therapy for 4 weeks followed by levodopa infusion and reassessment. MAIN OUTCOME MEASURES: Change in finger-tapping speed, measured using the area under the curve (AUC) for finger taps per minute across time; peak finger-tapping speed; duration of response; time to "ON" (defined as a 10% increase in finger-tapping speed above baseline); walking speed; and dyskinesia AUC. RESULTS: Pramipexole with levodopa infusion increased finger-tapping speed beyond the change in baseline by a mean (SE) of 170 (47.2) per minute x minutes (P = .006) and more than doubled the AUC for finger-tapping speed. Pramipexole increased peak finger-tapping speed by a mean (SE) of 18 (8.5) taps per minute (P = .02) and improved mean (SE) walking speed (15.9 [0.70] vs 18.9 [0.70] seconds, P = .004). Pramipexole prolonged duration of response after levodopa infusion and shortened time to ON. Pramipexole increased mean (SE) baseline dyskinesia scores (26.0 [5.85] vs 12.1 [5.85] points, P = .05) and peak dyskinesia scores with levodopa infusion. CONCLUSIONS: Pramipexole augmented the motor response to levodopa beyond a simple additive effect and increased the severity of levodopa-induced dyskinesia. When considering a combination of these therapies, an appropriate balance should be maintained regarding gain of motor function vs worsening of dyskinesia. Trial Registration clinicaltrials.gov Identifier: NCT00666653.

Page last updated: 2010-10-05

-- advertisement -- The American Red Cross
 
Home | About Us | Contact Us | Site usage policy | Privacy policy

All Rights reserved - Copyright DrugLib.com, 2006-2017