Enteral Levodopa/Carbidopa infusion in advanced Parkinson disease: Long-term exposure

Objectives: In patients with advanced Parkinson disease, levodopa/carbidopa formulated as a gel suspension (Duodopa) permits continuous delivery into the small intestine using a portable pump, resulting in less variability in levodopa concentrations and fewer motor fluctuations and dyskinesias than with oral levodopa administration. This is a retrospective analysis of the long-term clinical experience with this agent. Methods: All but 1 of the patients who had received enteral levodopa infusion treatment between January 1, 1991, and June 30, 2002, consented to a review of their hospital charts. Results: Of the 65 patients with initial testing of the treatment, 86% opted for continued treatment via percutaneous endoscopic gastrostomy or gastrojejunostomy. Total exposure to levodopa infusion was 216 patient-years (mean, 3.7 years). Maximum treatment duration was 10.7 years. Fifty-two patients were treated for 1 year or longer. The adverse effect profile of levodopa/carbidopa infusion was similar to that observed with oral administration of levodopa. Seven deaths occurred, all considered unrelated to the treatment. Intestinal tube problems, including dislocation of the intestinal tube to the stomach, were the most common technical problem, occurring in 69% of the patients during the first year. The optimal daily dose of levodopa decreased by an average of 5% during follow-up. Conclusions: The safety of enteral infusion of levodopa/ carbidopa formulated as a gel suspension was found acceptable. For most patients, the technical challenges posed by the enteral infusion system were offset by the improvement in motor fluctuations and dyskinesias offered by this technique.