The effect of complimentary and alternative medicine products on laboratory testing

A multi-billion dollar industry has evolved over the last decade based on herbal product sales with an underlying belief that herbals are natural and therefore safe. The herbal product industry is essentially unregulated and producers are not required to follow good manufacturing practices (GMP). Batch to batch product variation, heavy metal and pesticide contamination, and even therapeutic drug contamination are problematic. Compounding these manufacturing issues are drug to drug and drug to herbal interactions that can cause cytochrome induction or inhibition. It is important for physicians to query their patients on herbal use and educate them on the potential adverse reactions. Herbals have been used for thousands of years and undoubtedly have demonstrated health benefits. However, more research is needed to gain an understanding of the complexity issues from mechanism of action to interference with clinical laboratory testing.