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Drug Interactions

What is a drug interaction?

A drug interaction is a change in the way that a medicine works when you take it with another medicine. Alcohol, tobacco, vitamins, natural remedies, and certain foods may also interact with your medicines. Some prescription and nonprescription medicines may have a drug interaction when taken together.

If you have a drug interaction:

The drug may not work as well as it should.
The drugâ€™s effect may be increased.
You may have different side effects.

Sometimes drug interactions are helpful. For example, some medical problems, like high blood pressure, are treated with 2 medicines that work together. Taking low doses of 2 medicines may be safer than taking a higher dose of 1 medicine. Higher doses of medicine can sometimes cause more side effects.

What is the cause?

Any time you take a new medicine there is a chance it will interact with other medicines you take. To avoid problems caused by drug interactions, your healthcare provider and pharmacist need to know about all of the medicines, herbal remedies, vitamins, and other supplements you take.

How can I prevent drug interactions?

Follow the directions that come with your medicine, including information about food or alcohol. Make sure you know how and when to take your medicine. Do not take more or less than you are supposed to take.
Try to get all of your prescriptions filled at the same place. Your pharmacist can help make sure that all of your medicines are safe to take together.
Keep a list of your medicines with you. List all of the prescription medicines, nonprescription medicines, supplements, natural remedies, and vitamins that you take. Tell all healthcare providers who treat you about all of the products you are taking.
Many medicines have side effects. A side effect is a symptom or problem that is caused by the medicine. Ask your healthcare provider or pharmacist what side effects your medicines may cause and what you should do if you have side effects.

If you have any questions, ask your healthcare provider or pharmacist for more information. Be sure to keep all appointments for provider visits or tests.

Developed by RelayHealth.

Adult Advisor 2015.1 published by RelayHealth.
Last modified: 2014-10-30
Last reviewed: 2014-10-30

This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.

Drug Interactions: References

Drug Interactions: What You Should Know. (2013). FDA.gov. Retrieved 10/2014 from http://www.fda.gov/ForConsumers/ConsumerUpdates/ucm096386.htm.

Drug Interaction Checker: Medscape: http://reference.medscape.com/drug-interactionchecker Accessed October 5,2014

FDA.gov. – Drug Interactions: What You Should Know â€“ no author listed, last updated 09/25/2013. Accessed 7/8/2014 – http://www.fda.gov/drugs/resourcesforyou/ucm163354.htm

Institute for Safe Medication Practices â€“ General Advice on Medicine Use â€“ no author or date listed. Accessed 7/8/2014 – https://www.ismp.org/consumers/brochure.asp

FDA.gov. Drug Interactions: What You Should Know. 6/30/2012. Accessed 7/8/2013 from http://www.fda.gov/drugs/resourcesforyou/ucm163354.htm.

Drug Interactions: What you should know. US Dept of Health and Human Services, Food and Drug Administration. 4/30/2012. Accessed 6/30/2012 from http://www.fda.gov/drugs/resourcesforyou/ucm163354.htm.

Federal Citizens Information Center. Drug Interactions. 1/2002. Accessed 1/31/2011 from http://www.pueblo.gsa.gov/cic_text/health/drug-interactions/druginte3.htm.

Merck Manual. Drug Interactions: Factors affecting response to drugs. Merck Manual Online Medical Library. April 2007. Accessed Jan. 28, 2010 from http://www.merck.com/mmhe/sec02/ch013/ch013c.html.