Every day, millions of Americans use over-the-counter medicines for relief from headache or arthritis pain, coughs and colds, flu, and upset stomach. These over-the-counter medicines are effective, widely available, convenient, and cost-effective.
It is important to treat all of your medicines seriously and read all of the instructions carefully. This can help you avoid problems that may occur with all medications, including over-the-counter medicines.
Drug-drug interactions happen when a drug interacts, or interferes, with another drug. This changes the way one or both of the drugs act in the body, or causes unexpected side effects. The drugs involved can be prescription medications or over-the-counter medicines. They can even be things like vitamins and herbal products.
Sometimes when two drugs interact, the overall effect of one or both of the drugs may be greater than desired. For example, both aspirin and blood thinners like warfarin (Coumadin) help to prevent blood clots from forming. Using these medications together may cause excessive bleeding.
Other times, the overall effect of one or both of the drugs may be less than desired. 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 it may not work at all.
Drug-food interactions happen when a prescription medication or over-the-counter medicine interacts, or interferes, with something you eat or drink.
Drug-disease interactions happen when a prescription medication or over-the-counter medicine interacts, or interferes, with a disease or condition that you have. For example, decongestants, which are found in many cold remedies, may cause your blood pressure to go up. This may be dangerous for people with high blood pressure.
Your risk of having a drug interaction depends in large part on how many medicines you are taking. Fortunately most of these interactions can be prevented. By taking a few simple steps, you can protect your health and avoid serious problems.
Read the labels of all over-the-counter medicines. Look for the section called “Drug Interaction Precaution.” If you don't see it, don't assume that no interactions will occur. Read all the information carefully to be sure.
Tell all of the doctors and pharmacists you visit about all of the prescription medications and over-the-counter medicines you use. Use a Personal Medication Record to write down information about the medicines that you use. Be sure to include those you take every day as well as those you use only once in a while. If you use vitamins or herbal products, be sure to write them down, too.
Before taking any new medication, talk to your doctor or pharmacist. Ask whether it is safe to take the new medicine with other prescription medications, over-the-counter medicines, vitamins, or herbal products that you are taking. Ask if there are any foods, drinks, or medications you should avoid while taking the new medicine. Never use prescription medicines that belong to another person, even if that person seems to have the same health problem you have.
Ask your doctor or pharmacist for advice on over-the-counter medicines. Your doctor or pharmacist will help you choose the medicine that best meets all of your health needs. If you can, buy your over-the-counter medicines at the same pharmacy where you have your prescriptions filled. That way, the pharmacist can check your records to see if the over-the-counter medicines you buy could interact with the prescription medications you take.