Drug Therapies for Non-motor Symptoms and Gut PD

This chapter focuses on pharmacologic therapies in gut PD, starting from the effects of anti-PD drugs on the gut, their intricate and time-sensitive pharmacodynamics, and leading to a description of various options to be considered, including direct delivery of levodopa to the gut to mitigate side effects of over- or undertreatment. The panoply of drugs used to manage gut PD is then discussed in detail, highlighting the caveat that very few of these agents are specifically studied or approved in symptomatic management, which largely remains empirical yet frequently effective in improving the quality of life of such patients. Juxtaposed to these therapies are diet and lifestyle adjustments and other therapies frequently used as adjuncts.