New Study Warns of Possible Dangerous Interactions Between Herbal Supplements and Prescription Medications

In our never-ending quest to be healthy, many people take herbal supplements to boost their physical and mental health, memory, energy, digestion, and heart health, among other things. Supplements are marketed and accepted as part of a healthy diet so most people never question their safety, but a new study examines whether taking herbal supplements along with certain prescription medications can be a dangerous, even deadly, combination.

Researchers from the South African Medical Research Council recently published their findings on this issue in the British Journal of Clinical Pharmacology. Most patients in the study suffered from heart disease, kidney transplants, or cancer, and were taking statins, chemotherapy drugs, or anti-rejection drugs to treat their particular medical condition. Many patients reporting adverse drug reactions were also being treated for depression, anxiety, or other psychological disorders with anti-depressants, anti-anxiety, anti-psychotic or anticonvulsant medications.

After evaluating 49 cases of adverse drug reactions, researchers found “probable” herbal supplement/prescription drug interactions in 51% of the adverse reaction reports while 8% were deemed “highly probable”, 37% classified as “possible”, and only 4% regarded as “doubtful.” Researchers concluded herb-drug interactions could make prescription drugs less effective, possibly toxic, and even deadly, for patients taking herbal supplements and certain prescription medications.

For example, some organ transplant patients taking anti-rejection drugs and herbal supplements suffered organ rejection, while chemotherapy patients taking supplements containing echinacea, chokeberry juice, or ginseng reported negative side effects. Many patients taking anti-depression medications complained of increased depression after taking herbal supplements, while patients taking the blood thinner warfarin experienced “clinically significant interactions” when also taking herbal supplements containing chamomilla, goji juice, cranberry, safe, flaxseed, or St. John’s wort. One patient taking anticonvulsant medications died of a seizure, which researchers determined was due to negative effects on his metabolism after taking the herbal supplement Ginkgo biloba.

Because the study sample size is so limited, researchers urge additional studies with actual patients and in the laboratory to determine a more definitive connection between herb-drug interactions. Additional research is critical so drug makers and regulatory agencies can update drug safety labeling so that healthcare professionals and patients know what herbal supplements to avoid when also taking certain prescription medications in order to eliminate dangerous and deadly herb-drug interactions.

This study further demonstrates the importance of keeping your healthcare provider and pharmacist well informed about any dietary or herbal supplements, over-the-counter medications, and vitamins, you are taking in addition to your prescribed medicines. It’s easy to keep an updated list on your smartphone which you can reference any time you’re at the doctor or picking up a prescription. Although you may believe you’re doing something healthy by adding herbal supplements to your diet, you may actually be undermining the effectiveness of necessary life-saving prescription medications, or making them toxic to your system.