This volume provides information about herb-drug interactions that may arise as a result of the increasing interest in medicinal plants or herbal products and the concomitant use of conventional drugs. Medicinal plant-drug interactions are inevitable, especially when the elderly use medicinal plant products in addition to polypharmacy. Concurrent consumption of herbal products and conventional drugs is a serious concern. Over-the-counter herbal drug's doses can inhibit the metabolism of conventional drugs, increasing plasma levels of the drug. This book highlights evidence on herb-drug interactions from a systematic review, providing rapid access to information on their clinical use.