• Medical Safety: Side Effects & Interactions


    Medication safety is best achieved through open and honest conversations between a doctor and patient. If, as a patient, you find challenges to taking your medication as prescribed or have concerns, discuss these with your physician. Your physician will tap his or her experience helping other patients and professional expertise to recommend tools and suggestions to help you. Together, you can stay on track with taking prescribed medications, address any side effects and prevent potentially harmful drug interactions.

    Side Effects

    Trust your intuition: if a side effect seems serious, get help right away. However, do not stop taking a medication without consulting your doctor. You should make your doctor aware of any side effects you are experiencing. Many side effects are better than a cardiovascular event, such as a heart attack or stroke. Contact a doctor right away if you are experiencing serious side effects. Many of these will be listed on your medication information pamphlet or prescription bottle label.

    You can learn more about side effects and interactions that have been associated with certain types of cardiovascular medications in the chart provided here.

    If you find yourself struggling with adhering to your medication plan for any reason, talk to your doctor. Do not be embarrassed or worry about being scolded. Your safety is most important, and that means that you and your doctor must work together to find a solution.


    Sometimes researchers discover that certain drugs, foods, vitamin or herbal supplements, alcohol and other medical conditions can affect one another and can make a medication less, or more, powerful than was intended or lead to other side effects. For example, researchers have discovered an interaction between clopidogrel (sold under the brand name Plavix) and proton-pump inhibitors (a group of medications used to treat gastrointestinal disorders including Prilosec and Nexium, for example). Proton-pump inhibitors can reduce the effectiveness of clopidogrel.

    Other times patients do not realize they need to tell their physician about everything they are taking, including over-the-counter medications, vitamins, herbal supplements and hormone-based birth control. Forgetting to tell your physician about supplements and medications, or feeling too embarrassed to do so, can have serious consequences. For example, St. John's wort, an herbal treatment many try for depression, is known to interact with several heart medications, including warfarin (Coumadin) and clopidogrel (Plavix) and could result in increased risks of bleeding. Many of the most popular herbal supplements can lower or increase the effectiveness of cardiovascular medications, or cause other effects such as higher blood pressure or a change in heart rate.

    Both examples describe interactions--when substances behave differently in combination from how they would on their own. Be sure to talk with your cardiologist and primary care physician about everything you are taking, including over-the-counter medications, vitamins, herbal supplements and hormone-based birth control, and ask about possible interactions.

    Potentially Dangerous Interactions

    Hormone-Based Contraceptives

    Birth control pills may place women at higher risk of high blood pressure and blood clots that can cause stroke or heart attack. Women over age 35, smokers, and women with high blood pressure, diabetes or unhealthy cholesterol levels are most at risk. The birth control patch may pose an even greater risk because of its higher levels of estrogen.

    The connection between birth control pills and risk of heart disease remains unclear. If you have other risk factors, such as a history of heart disease in your family or if you are a smoker, talk to your physician about your concerns and options.

    Erectile Dysfunction (ED) Medication

    Erectile dysfunction (ED) is fairly common among men with heart disease, but if you have ED and are taking medication for it, it is very important that you tell your doctor because if you have any of the following conditions, ED medications may not be advised:

    • Certain high-risk heart problems, including chest pain (angina), heart failure, abnormal heart rhythms (arrhythmias) or a recent heart attack.
    • Uncontrolled high or low blood pressure
    • A history of stroke within the last six months
    • Eye problems, such as retinitis pigmentosa
    • Sickle cell anemia, leukemia, multiple myeloma, or another health problem that can cause an erection that won't subside (priapism)

    Side effects from any of these medications may include headache, flushing, indigestion or nausea, stuffy or runny nose, back pain and muscle aches (with Cialis), and temporary vision changes (with Viagra). It is unlikely that you’ll have a serious side effect, but if you have a sudden loss of hearing or vision, or an erection that lasts longer than four hours, seek medical help immediately.

    Several web databases provide information on drug interactions, for example, AARP’s drug interaction checker, but the best way to avoid dangerous interactions is to speak with your physician and disclose all medications and supplements that you are taking.