Long-term intraduodenal infusion of a water based levodopa-carbidopa dispersion in very advanced Parkinson's disease

Objective - To evaluate the effects of continuous duodenal infusion of levodopa over time on the disabling fluctuations in motor performance in advanced parkinsonian patients. It has earlier been demonstrated that these fluctuations can be reduced by keeping the plasma concentration of levodopa constant. Material and methods - In view of the low water solubility of levodopa a stable dispersion of the drug was developed and used for continuous intraduodenal infusion in patients with advanced Parkinson's disease. Nine patients were evaluated with respect to an optimal oral treatment, during nasoduodenal infusion by a portable pump and then followed for 6 months to 2 1/2 years when treated via transabdominal infusion. Upon each test occasion, over 2 non-consecutive days, objective movement analysis by means of an opto-electronic system was applied every 15-20 min and video recordings performed twice every h. On several test occasions plasma levodopa concentrations were analysed every 15 min. Results - The patients showed improvement and decreased variance of their motor function. In the 2 patients followed over a period of 2 1/2 years levodopa plasma concentration showed reduced fluctuations on infusion and the levodopa consumption as well as mean levodopa plasma concentration decreased. Conclusion - Continuous duodenal infusion of levodopa is an alternative treatment strategy for patients with advanced Parkinson's disease when conventional therapy has failed.