Vaccinium myrtillus, known as bilberry, is closely related to blueberry. Like its relative, bilberry is used to make jams, pies, syrups and other tasty concoctions. Bilberry also has a long history of use as an herbal remedy, including for some cardiovascular conditions that are conventionally treated with the drug warfarin, commonly known as the brand Coumadin. Research is lacking to confirm these benefits, according to the U.S. National Institutes of Health at its website MedlinePlus. Consult with a qualified health care provider before beginning any herbal therapy.
Cardiovascular Uses
Bilberry has been used traditionally to treat heart disease, chronic venous insufficiency and atherosclerosis, a condition in which fatty material builds up and hardens inside the arteries. Chronic venous insufficiency can cause leg swelling and pain, varicose veins and skin ulcers. Many Europeans with this condition take a standardized bilberry extract called vaccinium myrtillus anthocyanoside, according to the University of Maryland Medical Center, or UMMC.
Active Components
Bilberry contains several active chemical components, including anthocyanosides. Research with animals shows that anthocyanosides may improve blood flow and strengthen blood vessels, according to the UMMC. Components called coumarins may prevent platelets from clumping and blood from clotting, explains the Memorial Sloan-Kettering Cancer Center. The medicine Coumadin is classified as an anticoagulant, and it also decreases clotting ability of the blood.
Safety
Bilberry supplements are generally safe in recommended doses for short periods of time, according to MedlinePlus. No serious side effects are associated with bilberry, but if taken in large doses, bilberry or the leaf extract theoretically can increase the risk of abnormal bleeding. Although MedlinePlus notes a lack of reliable published reports of bleeding with the use of bilberry, the website recommends that people with bleeding disorders or taking medications or supplements that increase the risk of bleeding be cautious about taking bilberry.
Caution
Taking large doses of bilberry could cause problems if you also take Coumadin, as noted by MedlinePlus, since Coumadin increases the risk of abnormal bleeding. Doctors prescribe this medicine for patients with certain types of irregular heartbeat, with prosthetic heart valves, and who have experienced a heart attack. It can prevent or treat venous thrombosis, which is a blood clot in a vein, and pulmonary embolism, a blood clot in the lung. People taking Coumadin must be careful not to become cut or injured, because the blood-thinning effects can lead to severe bleeding that can even be life-threatening.
Other Possible Interactions
Several other medications may not be safe to take along with large doses of bilberry because of their anticoagulant effects, explains MedlinePlus. Some of these include aspirin, ibuprofen, naproxen, heparin and clopidogrel. Increased bleeding risk is also associated with the herbs ginkgo biloba, garlic and saw palmetto.
