Natural Blood Thinners

Aloe. In one case, a woman taking an aloe supplement bled heavily after oral surgery. There's also a risk of bleeding if you take aloe with nonsteroidal anti-inflammatory drugs (NSAIDs) like aspirin or ibuprofen.

Cranberry. There are documented cases of cranberry supplements interacting with warfarin. This can lead to bleeding.

Feverfew. Lab studies of platelets show it can affect their ability to stick together and form clots.

Garlic. Animal and human studies show it can slow blood clotting and lead to bleeding.

Ginger. One study found high doses of ginger affected clotting. More research is needed, but there’s also evidence it can raise your risk of bleeding if you're taking warfarin.

Ginkgo. Research shows it can slow clotting. It’s also led to bleeding in people who took it alone or with NSAIDs.

Meadowsweet. There are no reports of meadowsweet interacting with warfarin or NSAIDs. But it has a compound called salicylate that affects how well platelets can stick together.

Turmeric. Curcumin, one of turmeric's active ingredients, has antiplatelet effects.

White willow. This supplement has aspirin-like effects in the body. That means it can keep platelets from sticking together. There's no documented evidence of it interfering with warfarin.

Chamomile. This herb contains the compound coumarin. Warfarin has a man-made version of coumarin in it. But more research is needed to find out if it has any effect on blood clotting.

Fenugreek. Like chamomile, fenugreek contains coumarin. But more research is needed to find out if it has any effect on blood clotting.

Red clover. There's limited research about this supplement, but it also has coumarin. But more research is needed to find out if it has any effect on blood clotting.

Dong quai. It contains several compounds that come from coumarin. It has been shown to worsen bleeding in people taking warfarin.

Evening primrose oil. Animal studies show it slows the clotting process and stops platelets from sticking together. So it may make you bleed more during and after surgery, and when taken with warfarin or NSAIDs. More research in humans is needed.

Ginseng. Some lab studies show it can thin the blood, but more research is needed to know for sure.

*Courtesy of WebMD.