Over-the-counter (OTC) medicines are used to treat a variety of conditions, from headaches to stomachaches. These medicines are easily accessible because you do not need a prescription from a doctor to purchase them. Therefore, OTC medicines are an appealing treatment option.

However, it is important to remember that just like prescription medicines, OTC products can cause serious side effects especially if they are taken wrong or with other medicines. Here are a few tips to help you make safe choices and reduce your risk of harm when using OTC medicines.

1. Consult your doctor or pharmacist before purchasing an OTC product. Your doctor and pharmacist can help guide you in selecting an appropriate OTC medicine based on your medical history. They should be aware of any allergies you have or other prescription or OTC medicines you are taking. Be sure to tell them about any herbal supplements, vitamins, or alternative products you may be using. Your doctor or pharmacist will use this information to recommend an OTC product for you.
2. Read the label carefully. The US Food and Drug Administration (FDA) requires drug manufacturers to include specific information on OTC medicines. This important information is found in the Drug Facts label on the medicine package or container. The label includes active ingredients; purpose (what it is for); uses; warnings; directions – when, how, and how often to take; age restrictions, and other information including inactive ingredients. ¹ If you are unsure how to read the Drug Facts label, ask your pharmacist for help. For more information on how to read an OTC label, see ISMP’s article, Anatomy of an OTC Medicine Label.
3. Do not take medicines with the same active ingredients. The active ingredient is the component in the drug that works to treat the problem. The active ingredient is listed on the Drug Facts label. The active ingredient may be in a number of different OTC medicines. For example, OTC pain relievers such as Advil and Motrin both have the active ingredient ibuprofen, so they should not be taken together. Taking medicines with the same active ingredient can lead to serious side effects or a life-threatening overdose. So, when purchasing OTC products, always compare labels. Once home, check the new product's active ingredients against any OTC or prescription medicines you already have. If you are unsure, ask your pharmacist if it is okay to take the OTC product with the other medicines you take.
4. Only treat the symptoms you have. Some OTC products contain more than one ingredient. Each active ingredient treats a different symptom. For example, Tylenol (a pain reliever/fever reducer) and Tylenol Cold & Sinus (often used to treat a cold and sinus congestion) both contain the active ingredient acetaminophen, so they should not be taken together. Tylenol Cold & Sinus also contains another active ingredient, pseudoephedrine which helps relieve congestion. To avoid taking unnecessary medicines and reduce your risk of side effects, chose a product that only treats the symptoms you have.
5. Keep a current list of medicines you take. OTC medicines, vitamins, supplements, and herbal products can interact with each other and some prescription medicines. By having a current list of medicines you take, your doctor and pharmacist will be able to accurately check for interactions before prescribing or dispensing new medicines to you. They can also tell you which OTC products are safe to take with your other medicines, and which OTC products to avoid.
6. If you are pregnant or breastfeeding consult with your doctor before taking an OTC medicine. Some OTC medicines are harmful to a developing baby. Some medicines a breastfeeding mom may take can pass through her breast milk and may harm her baby. It is always best to ask your doctor before taking any medicine while you are pregnant or breastfeeding.
7. Remember herbal supplements are not the same as OTC medicines. Herbal supplements can be found in the OTC aisle, but unlike OTC medicines, FDA does not review them for safe use before they are marketed.² Herbal supplements can cause side effects, interact with other medicines you may take, and worsen a health condition. Many herbal supplements are labeled “natural,” but natural does not mean safe. Remember to always talk to your doctor or pharmacist before starting any herbal supplement.
8. Always check the expiration date. Never use medicines that are expired. According to FDA, a medicine can become less effective or more potent after its expiration date.³ Set aside a few days each year to throw away the expired medicines in your home. For information on how to properly dispose of expired or unused medicines, see FDA’s article, Where and How to Dispose of Unused Medicines.
9. Only use the measuring device that comes with the OTC product. Household measuring spoons and other kitchen utensils (e.g., teaspoons) should not be used to measure a dose of medicine. Using these items can result in taking more or less of a medicine than is recommended. Instead, always use the measuring device that comes with the OTC product. For more information, see ISMP’s Tips for Measuring Liquid Medicines Safely.
10. Seek medical attention if your symptoms get worse or you experience side effects. If your symptoms do not improve or if you feel worse after taking a few doses of an OTC medicine, contact your doctor. Continuing to self-treat can delay you from receiving the medical treatment necessary for what may be a serious health condition.

ISMP thanks Kimberly M. Gibson, Pharm D for her contribution to this Top Ten list.

References:

1) OTC Drug Facts Label. https://www.fda.gov/drugs/resourcesforyou/consumers/ucm143551.htm

2) Dietary Supplements. FDA.gov. https://www.fda.gov/Food/DietarySupplements/. Updated April 13, 2018. Accessed May 3, 2018.

3) Don’t Be Tempted To Use Expired Medicines. FDA.gov. https://www.fda.gov/Drugs/ResourcesForYou/SpecialFeatures/ucm481139.htm. Updated March 1, 2016. Accessed May 5, 2018.

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