Are herbal supplements part of your daily medication routine? Many people don’t think of herbal supplements as medication. But the ginseng you take for memory or the black cohosh for osteoporosis should be monitored just as closely as your prescription medications.

“Herbal medications can have adverse interactions when mixed with prescription medications or on their own,” said Jeff Anderson, PharmD, MS, BCPS, Director of Pharmacy Services at Yavapai Regional Medical Center (YRMC). “They are not harmless.”

For example, sipping wine or eating chocolate may cause adverse reactions in people who take St. John’s wort to lift their moods, Anderson said. Until recently, St. John’s wort was believed to work through the monoamine oxidase inhibition (MAOI) pathway to treat depression. MAOIs may also be used to treat Parkinson’s disease, anxiety disorders and social phobias.

People taking warfarin should avoid herbal products that may reduce the effectiveness of the blood thinner. Taking warfarin with natural supplements such as Ginkgo biloba or Vitamin E can increase the possibility of bleeding.

“Taking warfarin and ginkgo together should be avoided or done under physician supervision,” said Anderson.

While the therapeutic claims of herbal products aren’t reviewed by the Food and Drug Administration (FDA), consumers should look for the United States Pharmacopeia (USP) Verified Mark when purchasing herbals.

“This insignia indicates that the product has passed rigorous testing and auditing criteria,” he said. “If it doesn’t have the USP Verified Mark, it could contain some unnecessary or unwanted ingredients that can have negative health effects.”

Here are other popular herbal supplements and their potential interactions:

  • Black Cohosh – Black cohosh has a history of use for rheumatism (arthritis and muscle pain). More recently, it has been used for hot flashes, night sweats and other symptoms of menopause. It’s also been used for menstrual irregularities and premenstrual syndrome. There are concerns about interactions between black cohosh and some medications, but the risk appears to be small.
  • Cranberry – This popular product is most often used to prevent and treat urinary tract infections. Be sure to avoid cranberry juice and cranberry products if you take anti-coagulants as they can change how they work.
  • Echinacea – Feel a cold coming on? That’s when many take Echinacea based on the idea it may stimulate the immune system to more effectively fight infection. While studies don’t support this, supplements formulated with a standardized Echinacea extract do not appear to interact with most conventional drugs.
  • St. John’s Wort – For centuries, this supplement was used to improve mental health and nerve pain. St. John’s wort also has been used for malaria, as a sedative, and as a balm for wounds, burns and insect bites. Today, St. John’s wort is used as a remedy for depression, anxiety and/or sleep disorders. However, there are clinically significant interactions documented with St. John’s wort and many medications so it’s important to talk to your physician before starting this supplement.
  • Ginkgo Biloba – This product is taken for memory impairment and tinnitus (ringing in the ears). If taken in low doses, there is very little risk for interaction with prescribed medications. Higher daily doses may increase the potential for interactions with medications including anti-coagulants.

What’s the bottom line for people taking supplements or herbals? According to Anderson, always check with your physician before taking them. Additionally, your pharmacist can provide information about potential interactions.