Unwanted effects and interaction of intrajejunal levodopa/carbidopa administration

Introduction: Levodopa is the most effective treatment for Parkinson's disease. After a number of years on treatment, fluctuations and dyskinesias may develop. Hence, invasive treatment measures are often needed (escalation therapy). Areas covered: Twenty years ago, a levodopa/carbidopa intestinal gel (LCIG) that can be infused directly into the jejunum was developed. This provides for continuous dopaminergic stimulation. For the past 10 years, LCIG has been licensed in some countries and its marketing approval is pending in the USA. It is endowed with very good efficacy, and in studies, it has proven to be superior to oral drug treatment. Continuous dopaminergic stimulation is also assured, and fluctuations and dyskinesias are significantly reduced. However, this technique involves an invasive procedure with percutaneous endoscopic gastrostomy and attendant surgical and postsurgical complications. Besides, there are problems related to the pump and tube. Vitamin deficiency and polyneuropathies are other drawbacks. Expert opinion: LCIG is a beneficial and very useful treatment option as escalation therapy for Parkinson's disease. While the side effects are not insignificant, they are justifiable in view of the severity of the disease. Attention must be paid, in particular, to malabsorption, with monitoring at baseline and in the course of treatment.