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A Must-Know Guide to Drug-Drug Interactions

By Floria, Barbara

Drug-drug interactions occur when one drug interacts or interferes with one or more other drugs.

Such interactions are dangerous because they can alter the way one or both of the drugs act in the body. They can also cause unexpected side effects.

A common misperception is that only prescription medications have the potential to interact with each other. But over-the-counter medicines also may result in drug-drug interactions when combined with prescription medications or with other over-the-counter medicines, vitamins or herbal products.

The following information can help you avoid drug-drug interactions.

Common interactions

Not all drug-drug interactions are alike. Sometimes when drugs interact, the overall effect of one or more of the drugs may be greater than desired.

For example, both aspirin and blood thinners such as warfarin or Coumadin help prevent blood clots from forming. Using these medications together, however, may cause excessive bleeding.

With other combinations of medicine, the effectiveness of the drugs may be reduced. For example, certain antacids can prevent many medicines from being absorbed into the bloodstream. If this happens, the medicine may not work as well -- or may not work at all.

Some of the more common symptoms of drug-drug interactions include nausea or upset stomach, headache, heartburn and dizziness.

Keep a list

If you experience any reaction that seems out of the ordinary after taking any medication, consult your local pharmacist and make him or her aware of all of the medicines and remedies you're taking. Herbal supplements can add to the risk of drug-drug interactions.

In fact, herbal products and supplements don’t have to be tested to prove they work well and are safe, and may be dangerous for individuals with certain health problems. The American Academy of Family Physicians recommends that you should be especially cautious about using herbal health products or supplements if you take any of the following types of drugs:

  • Drugs to treat depression, anxiety or other psychiatric problems

  • Anti-seizure drugs

  • Blood thinners

  • Blood pressure medicine

  • Heart medicine

  • Drugs to treat diabetes

  • Cancer drugs

In the case of a serious reaction, call 911 for emergency medical treatment.

The following steps can help you and your family avoid drug-drug interactions:

  • Read the label. If you don't, you may take an incorrect dosage or overlook potential side effects.

  • Know the risks. Make sure you know the benefits and the potential risks of medications you take. Look specifically for the section called "warnings" on the labels of over-the-counter medicines.

  • Ask questions. Talk to your health care provider or pharmacist before taking any new medication. Ask whether it's safe to take the new medicine with other medications, vitamins or herbal products you already take -- regularly or even occasionally. Keep a list of all the drugs you take and share it with your doctors and your pharmacist.

  • Pick a pharmacy. Use one pharmacy for all of your family's medication needs. Doing so allows your pharmacist to look for and help you avoid drug-drug interactions.

Medical Reviewer: [Byrd, Sylvia RN, MBA, Godsey, Cynthia M.S., M.S.N., APRN, Lambert, J.G. M.D., Oken, Emily MD] Last Annual Review Date: 2008-06-06T00:00:00-06:00 Copyright: Copyright Health Ink & Vitality Communications

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