Cardiovascular disease is the number one cause of death in the U. S. It encompasses a wide array of conditions, including coronary heart disease, high blood pressure and heart rhythm problems (arrhythmias). Many types of drugs are used to help manage cardiovascular disease, including blood thinners, aspirin and medications to open your blood vessels (vasodilators), lower your cholesterol (statins and fibrates) and reduce water retention (diuretics).

In the past, some doctors have been nervous about combining dietary supplements with these drugs. However, as consumers are becoming more proactive in their health and medication use, they are also turning to natural therapies to accompany lifestyle changes that prevent and treat heart-related conditions. This in turn requires doctors to be up to date on the scientific evidence for such therapies and possible interactions in order to give you the highest level of care. 

Patients should also be proactive in understanding potential interactions. Here are some key drug-supplement interactions to be aware of.

Coumadin, the brand name for the blood-thinning drug warfarin, is a common drug used to prevent blood clots from forming. Many drugs, prescription and nonprescription, and foods interact with Coumadin. Tylenol and ibuprofen may enhance the action of the drug, which can lead to life-threatening bleeding. Foods that are high in vitamin K, such as green leafy vegetables, broccoli and celery, may alter the action and effectiveness of this drug.

Other foods and supplements that may interact with warfarin and cause an increased risk of bleeding include garlic, cranberry juice, fish oil, onion, cloves and chamomile. However, if you have incorporated these substances into your daily diet before starting warfarin therapy, just remember not to drastically decrease or increase your intake of them. Your warfarin dose will be adjusted based on blood test results, so a consistent diet is key. It is crucial that you discuss all supplement and diet changes with your doctor and pharmacist.

Red yeast rice is a common supplement used to lower cholesterol. Although there is good evidence for its effectiveness, it should be noted that this supplement has many drug interactions. When used with warfarin, it may increase your risk of bleeding. When combined with statins, it may increase the risk of rhabdomyolysis, or muscle breakdown and pain. Red yeast rice may also increase liver enzyme levels in your body; therefore, you want to be careful when using it with other drugs that may harm your liver, such as fenofibrates, phenytoin, aspirin and acetaminophen.

Fish oil’s heart-health benefits are supported by scientific evidence, but combining this supplement with anticoagulants may also increase your risk of bleeding. Combining fish oil with high blood pressure or cholesterol lowering drugs may also have an additive influence in your body, meaning it could enhance the effects of the drug. Care must be taken because lowering your blood pressure or cholesterol beyond the goal set by your doctor may lead to other health concerns.

Coenzyme Q10 also has scientific support for the treatment of cardiovascular disease. However, certain drugs for heart disease such as statins, fibric acid derivatives for cholesterol (gemfibrozil) and beta blockers for high blood pressure may lower levels of CoQ10 in the body.

It’s important to note that common foods and supplements may alter how quickly the liver breaks down medications. For example, consuming grapefruit juice along with certain medications, for example Coumadin and some high blood pressure medications, that are metabolized in the liver can alter the levels and effects of these drugs.

Before starting any drug therapies for heart disease, it is important to talk to your health care provider about all of the dietary supplements you are taking or plan to take, including herbs and vitamins.

For information about specific interactions, refer to the Wellness Times Resource Center.

Dr. Catherine Ulbricht is one of the founders of Natural Standard, a key Wellness Times content partner. Watch this video about Natural Standard featuring Dr. Ulbricht.