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  1. Special Features

Drug Interactions: Understanding the Risk

Do you take two or more prescription drugs or a prescription drug and over the counter drug together? If you do, this can cause more harm than good if you are not careful. 

Recognizing Drug InteractionsDrugInteractions 

Drug-drug interactions occur when two or more drugs – prescription and/or OTC -- react with each other. Some drug interactions can make the drug you take less effective. And some combinations of drugs can be dangerous. For example, mixing a drug you take to help you sleep (a sedative) and a drug you take for allergies (an antihistamine) can slow your reactions and make driving a car or operating machinery dangerous.

Not all drugs work in the same way in all people. You could be harmed and not helped by a drug designed to treat cold symptoms. For example, if you have high blood pressure, cold medications containing a decongestant may actually raise your blood pressure.

Food and Drug Interactions

There are also times that a drug should not be taken with certain foods or beverages. For example, some drug instructions will say not to drink a citrus juice, like grapefruit, when taking and others will instruct you not to drink alcohol.

Understand Your Drug and Possible Side Effects

You can reduce the risk of harmful drug interactions and side effects by understanding the drugs that you take. Every time you use a drug, take the time to learn about possible drug interactions and read the drug label.

Talk to your health care providers and pharmacist about all the drugs that you take. Discuss all OTC and prescription drugs, dietary supplements, vitamins, botanicals, minerals and herbals you take, as well as the foods you eat.

Also, read the package insert for each prescription drug you take. The package insert provides more information about potential OTC and prescription drug interactions. Before taking a drug, ask your doctor or pharmacist the following questions: 

  • Can I take it with other drugs?
  • What are the possible side effects and what to do if I experience them?
  • Should I avoid certain foods, beverages or other products? 

Did you know?

Because of the amount of time a particular drug stays in your body and due to its interaction with another drug you are taking, a pharmacist may advise you to take each drug at different times of the day.
Source: Adesola F. Adejuwon, Pharm.D, U.S. Food and Drug Administration


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