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Know Your Terms


A supplement is something that completes or enhances something else when added to it. In the medical world, supplements are often taken to remedy deficiencies in a person’s diet. Examples include vitamins, minerals, amino acids, and herbs.


A medication is a substance used for medical treatment. Often, medications are prescribed and used for a directed period of time.

The Danger Zone

Taking prescription drugs and supplements together can be dangerous. Medications and
supplements can interact in negative ways.

Research shows that supplements can prevent enzymes—substances in the body that accelerate chemical reactions—from breaking down a drug. When supplements stop enzymes from breaking down drugs, the medication can build up to potentially toxic levels that can lead to an accidental overdose. A supplement can also break down a drug at a faster rate, dissolving it before the medication has time to be effective.

It is important to check with your healthcare provider about the potential side effects of supplements when taken with medications.

Common Supplements with Negative Effects

Many supplements interact with prescribed medications. The following list features some of the more common over-the-counter supplements taken and the side effects they have on prescription drugs. You can always check to see what potential interactions your own prescriptions might have with supplements.


St. John’s wort is a popular herbal supplement used to counteract symptoms of depression. However, it can reverse the effects of drugs as varied as birth control pills, HIV medications, certain antidepressants, MAO inhibitors, and others.

2. KAVA:

Kava is commonly used to improve sleep, decrease anxiety and tame nervousness and stress. It should not be used with alcohol, other drugs or herbs, or any substance known to cause liver toxicity. Buprenorphine, which is often
used in medications that combat opioid addictions, will negatively react with kava, often leading to respiratory distress or coma.


Vitamin E is said to help balance cholesterol and repair damaged skin. But Vitamin E has also been known to
reduce the effects of cancer medications and increase the risk of side effects caused by blood thinners and immunosuppressants.


Melatonin is used to regulate the sleep cycle, manage high blood pressure, improve depression and more. However, more than 100 drug interactions can occur with melatonin. Patients using insulin or allergy medications,
or those who have blood clotting disorders, should not take melatonin.


Ginkgo biloba interacts with more than 500 prescription medications. The supplement’s main usage is to counteract symptoms of Alzheimer’s disease and Parkinson’s disease, and aid in memory support. But gingko biloba will alter medications metabolized through the liver and cause dangerous and sometimes fatal effects.

Preventing Interactions

Talking with your healthcare provider is the best way to prevent having supplements interact with prescribed medications. Keeping an open line of communication between you and your physician will lower the chances of
having a drug interaction.

Additionally, keep all of your prescriptions at one pharmacy. Your pharmacist can electronically screen and review your prescriptions. If you think you want to add a supplement to your diet, talk with the pharmacist before purchase. She or he can point you in the right direction to avoid possibly dangerous prescription-supplement interactions.