Under-hyped and over-hyped drug-dietary supplement interactions and issues.

Complementary and alternative medicine utilization continues to abound, as does the use of prescription medications. Thus, real and hypothetical concerns exist for potential drug-dietary supplement interactions. Several supplements, including kava and St. John's Wort, have the potential for adverse medication interactions, but there are also several supplements, such as fish oil, garlic, ginkgo, pygeum, and saw palmetto, whose adverse potential may have been embellished. Still, there are other common supplements, such as vitamin D, that are enjoying an impressive amount of attention and consumption but their potential for current or future toxicity seems considerable and concerning, especially with individuals with multiple non-communicating practitioners. Regardless, it is important to continue to monitor dietary supplements (not just herbal products) that may have interaction and toxicity issues, and to also educate patients and clinicians on other supplements that do not have these issues despite an earlier concern and avoidance based on a minimal number of laboratory studies or case reports.