Role of piperine in CNS diseases: pharmacodynamics, pharmacokinetics and drug interactions.

Introduction: Piperine, the major bioactive component from black pepper, has gained increasing attention for its beneficial effects in the central nervous system (CNS). However, its related pharmacodynamics and brain pharmacokinetics, as well as its interaction with other CNS drugs are lacking, which may hinder its therapeutic and safe use. Areas covered: The current review provides an updated summary on CNS activities of piperine, including anti-epileptic, anti-depressive and neurodegeneration protection effect. The brain pharmacokinetic properties of piperine together with the approaches to enhance its aqueous solubility were summarized. Considering the wide use of black pepper and the well-reported alteration on CYP and transporters by piperine, interactions between piperine and CNS drugs are also illustrated for the first time. Expert opinion: Although the CNS beneficial effects of piperine have been extensively studied in preclinical models, clinical evidence on its CNS application is barely available, which may be attributed to its limited aqueous solubility, unclear pharmacokinetic properties in humans and potential toxicities during long-term use at higher doses. Although beneficial interactions between piperine and certain CNS drugs were often reported in preclinical studies, more mechanistic studies with clinically relevant doses should be conducted to provide guidance on their clinical combination use.