Lack of efficacy of one serving of coca tea as add-on therapy to a single levodopa dose in Parkinson’s Disease patients: A pilot study.

SANTIAGO PEREZ-LLORET; MARCELA LOPEZ; MALCO ROSSI; MARCELO MERELLO; ANDREW LEES

Nueva Orleans, USA

Congreso; Congreso Internacional de Movimientos Anormales; 2006

Objective: To test the efficacy of a small dose of cocaine in a double-blind cross-over design. Background: Dopamine transporter (DAT) inhibition significantly improves levodopa efficacy in Parkinson Disease. Cocaine is a potent DAT inhibitor. Methods: Six Parkinson’s Disease patients (mean age 66 years, range 55-80 years; 66% females; mean disease duration 11 years, range 6-17 years) were instructed to visit the out-patient clinic on two consecutive days after an overnight drug holiday and in fasting state. On each day an acute levodopa test was performed. In randomized order each patient received 200 ml of regular tea on one of the days and coca-tea on the other. Coca tea was prepared by adding 2 g of coca leaves to 200 ml of boiling water for 5-10 minutes (estimated cocaine dose: 9.7 mg). The coca leaves were then removed and the patient was allowed to drink the tea and take a levodopa pill, both teas tasted the same. The patient and the evaluating physician were blinded to treatment. Results: The area under the curve corresponding to UPDRS III score changes observed after levodopa dosing were 58 ± 37 points/hour (Mean ± SD) and 56 ± 32 points/hour for regular and coca tea respectively. The size effect of coca tea pretreatment was 2 ± 9 points/hour (p=0.6, Wilcoxon test). Coca tea did not affect dyskinesia frequency or intensity. One patient reported nausea and another patient drowsiness after the administration of regular tea and coca tea, respectively. No mood changes were observed. Conclusion: These results do not show any effect after small cocaine doses administered as an infusion for the improvement of the levodopa efficacy in Parkinson’s Disease patients. Studies with higher doses are warranted.