Radix Puerariae: an overview of its chemistry, pharmacology, pharmacokinetics, and clinical use

Radix Puerariae has been traditionally used for the treatment of diarrhea, acute dysentery, deafness and cardiovascular diseases. Yege (Gegen or Radix Puerariae lobatae), the dried root of Pueraria lobata (Wild.) Ohwi, has been widely used in China and, to a lesser extent, in Japan, Korea, and the United States. Although they have been classified into different categories in Chinese Pharmacopoeia, Yege is often used interchangeably in practice with Fenge (Radix Puerariae thomsonii), which is the dried root of Pueraria thomsonii Benth. Among various commercially available products of Radix Puerariae, injection of puerarin, the major isoflavone from Radix Puerariae, has been most widely used as a vasodilator for the treatment of angina and myocardial infarction. Considering the extensive clinical usage and recent alert of fatal herb-drug interaction of Radix Puerariae, the current review is proposed to cover its traditional applications, pharmacological activities, pharmacokinetics, clinical efficacy, and potential herb-drug interactions aiming to fill in the information gaps of this herb for frontline practitioners. Although various small, poorly designed clinical trials have demonstrated the safety, efficacy, and significant clinical benefits of Radix Puerariae, prospective randomized controlled clinical trials are needed to further establish its effective and safe use.