Understanding supplement and medication interactions
More people than ever before are taking vitamins and dietary supplements. According to a survey from the Council for Responsible Nutrition, 75 percent of Americans report consuming dietary supplements.
Not only are people taking supplements consistently, they're also combining them with multiple prescriptions and over-the-counter medications. This combination of dietary supplements and medication could potentially lead to serious side effects or make a medication less effective.
Be aware of the ingredients in your supplements
Dietary supplements contain a variety of ingredients: vitamins, minerals, amino acids, and herbs or other botanicals. Research has confirmed the health benefits of some dietary supplements, but not others.
The labeling on many dietary supplements gives the impression they are "natural" and therefore safe. However, "natural" does not necessarily equal "safe." While dietary supplements are regulated by the U.S. Food and Drug Administration (FDA), they are not required to undergo safety testing or FDA approval before they are sold and marketed. Most dietary supplements have not been tested in pregnant women, nursing mothers or children.
Stay safe when supplements and medication are taken together
While it's always important to monitor your body's response to supplements, it's even more vital to be aware of possible side effects from combining dietary supplements with prescription medications or medical procedures. Some dietary supplements can change the way medication is absorbed and metabolized, altering its potency. Some can increase the risk of side effects, like bleeding, or even change your response to anesthesia.
Combining dietary supplements and medications could have dangerous and even life-threatening effects. A few examples:
- St. John's Wort, an herbal supplement, can break down many drugs, including drugs for heart disease, depression and birth control pills. This reduces the drugs' effectiveness. Depending on the medication involved, the results can be serious.
- Warfarin is a common prescription blood thinner. Taken with a supplement such as omega-3 fish oils, it could increase the risk of bleeding in certain patients. The herbal supplement ginkgo biloba, aspirin, and the supplement vitamin E can each thin the blood. Taking any of these products together may increase the potential for internal bleeding or stroke.
- Many supplements have unwanted effects before, during and after surgery. Garlic, vitamin E and fish oil have blood-thinning effects. Some supplements can also interfere with anesthesia, including St. John's wort, ephedra, garlic, and ginseng to name a few.
- Antioxidant supplements, like vitamins C and E, might reduce the effectiveness of some types of cancer chemotherapy.
Talk to your doctor to reduce the risk of supplement interactions
Before you start taking vitamins or dietary supplements, it's important to talk to your health care provider. By knowing about any supplements, over-the-counter medications and prescriptions you may be taking, your primary care provider (PCP) will have a full picture of what you do to manage your health. To get the conversation started, you might want to consider discussing these four things:
- The reason you're taking the supplements.
- How you're taking them.
- The potential risk of taking the supplements.
- Their effectiveness.
In addition to speaking with your doctor about supplements, the FDA also suggests that you take these extra precautions:
- Ask yourself if the dietary supplement claims seem too good to be true, exaggerated or unrealistic.
- Watch out for extreme claims, like the vitamin will be a "cure-all" or "quick and effective."
- Be skeptical about personal testimonials from others who have used the product.
Learn more about dietary supplements on the FDA website. If you or a family member has an adverse reaction to a dietary supplement, report the problem to the FDA. To file a safety report online, visit the Health and Human Services website.