Interactions With Olive Leaf Extract & Blood Thinners

Fact Checked


Many people try to control health conditions by incorporating alternative remedies into their daily routines. Herbs and supplements are typically safe, however if you take a prescription medication, be careful. Drug interactions are common, but not always well documented. For example, olive leaf extract is a popular herbal remedy used to treat a variety of conditions, however, insufficient evidence exists regarding its interactions with drugs. Talk to your doctor before taking olive leaf extract while on blood thinners, as research indicates an interaction is possible.

Olive Leaf Extract

Most people are familiar with the health benefits of olives and olive oil, however, another part of this Mediterranean tree is also useful -- the leaf. The olive leaf and its extracts have been used medicinally and in teas for generations. In the 1800s, the olive leaf was a common treatment for malaria. Today, olive leaf extract is used to treat many health issues, including the common cold, the flu, bacterial infections and hypertension.

Blood Thinners

Blood thinners are used to prevent heart attacks, strokes and blood vessel clots. The two main types of blood thinners include anticoagulants, such as heparin and warfarin -- or Coumadin -- and antiplatelets, such as aspirin. Blood thinners interact with a variety of over-the-counter medications, prescription drugs, foods and supplements. Some of the items that cause interactions include Advil, Tylenol, multivitamins, garlic, ginkgo biloba, green tea and vitamin K–rich foods.

Olive Leaf Extract and Blood Thinners

Insufficient drug interaction evidence exists regarding olive leaf extract and blood thinners; however, care should be taken. Olive leaf extract has been shown to act as a vasodilator in rats. A vasodilator opens blood vessels and allows blood to flow more easily. In addition, another study showed that olive leaf extract inhibited platelets from sticking together during the clotting process in test tubes. More research is needed on human subjects to confirm these results; however, due to olive leaf extract's potential role in vasodilation and platelet activity, there may be an increased risk of bleeding if taken while on a blood thinner. Talk with your doctor before taking olive leaf extract.


Interactions can be dangerous, especially with blood thinners. If the medication is not working properly, your risk of clotting or bleeding may increase. Read packaging labels or talk with a pharmacist when choosing herbs, supplements and over-the-counter drugs. If you have any concerns about how something will react to the blood thinner you are taking, consult with your doctor.