Heparin (drug interactions)
Heparin is a widely used injectable anticoagulant that helps prevent blood clots, but it is important to be aware of potential drug interactions that may heighten the risk of bleeding. Certain herbal supplements and medications can influence the effectiveness of heparin or exacerbate its blood-thinning properties. For example, supplements like chondroitin, garlic, and ginkgo may have harmful interactions due to their own blood-thinning effects. Other substances such as phosphatidylserine and policosanol could potentially amplify heparin's anticoagulant effects, necessitating medical supervision when combined with heparin. Additionally, vitamin C may reduce heparin's blood-thinning effect, though the significance of this interaction is not fully determined. Caution is also advised when considering the use of white willow, as it contains salicylates similar to aspirin, which can increase the bleeding risk when taken with heparin. Furthermore, prescription medications—especially other anticoagulants, NSAIDs, and certain antibiotics—should be avoided while on heparin therapy to minimize complications. Overall, those on heparin should consult healthcare professionals before adding any new supplements or medications to their regimen to navigate these complexities safely.
Heparin (drug interactions)
- DEFINITION: A blood-thinning drug that is delivered by injection.
- INTERACTIONS: Chondroitin, dong quai, feverfew, fish oil, garlic, ginger, ginkgo, ginseng, PC-SPES, phosphatidylserine, policosanol, vitamin C, vitamin D, vitamin E, white willow, various prescription medication
Chondroitin
Effect: Possible Harmful Interaction
Based on chondroitin’s chemical similarity to the anticoagulant drug heparin, it has been suggested that chondroitin might also have anticoagulant effects. There are no case reports of any related problems, and studies suggest that chondroitin has at most a mild anticoagulant effect. Nonetheless, chondroitin should not be combined with heparin except under physician supervision.
Garlic
Effect: Possible Harmful Interaction
The herb garlic (Allium sativum) is taken to lower cholesterol, among many other proposed uses. Because garlic has a blood-thinning effect, it might be dangerous to combine garlic with heparin. Two cases have been reported in which the combination of garlic and the blood thinner warfarin doubled the time it took for blood to clot. Though warfarin thins the blood differently than heparin, there are concerns that garlic might interact similarly with heparin.
Ginkgo
Effect: Possible Harmful Interaction
The herb ginkgo (Ginkgo biloba) has been used to treat Alzheimer’s disease and age-related memory loss, among many other conditions. Ginkgo thins the blood by reducing the ability of blood-clotting cells called platelets to stick together. Because case reports have implicated the use of Ginkgo biloba in the development of serious bleeding abnormalities, combining ginkgo with heparin might be expected to intensify the danger.
PC-SPES
Effect: Possible Harmful Interaction
PC-SPES is an herbal combination that has shown promise for the treatment of prostate cancer. One case report suggests that PC-SPES might increase the risk of bleeding complications if combined with blood-thinning medications.
Phosphatidylserine
Effect: Possible Harmful Interaction
The supplement phosphatidylserine is promoted to treat Alzheimer’s disease and ordinary age-related memory loss. A test-tube study suggests that phosphatidylserine might amplify heparin’s blood-thinning effects. If this effect occurs inside the body, it could increase the risk of abnormal bleeding. Persons taking heparin should consult a doctor before taking phosphatidylserine.
Policosanol
Effect: Possible Harmful Interaction
Policosanol, derived from sugarcane, has been taken for hyperlipidemia and intermittent claudication. Human trials suggest that policosanol makes blood platelets more slippery, an action that could potentiate the blood-thinning effects of heparin, possibly causing a risk of abnormal bleeding episodes. A thirty-day double-blind placebo-controlled trial of twenty-seven persons with high cholesterol levels found that policosanol at 10 milligrams (mg) daily markedly reduced the ability of blood platelets to clump together. Another double-blind placebo-controlled study of thirty-seven healthy volunteers found evidence that the blood-thinning effect of policosanol increased as the dose was increased: the larger the policosanol dose, the greater the effect. Another double-blind placebo-controlled study of forty-three healthy volunteers compared the effects of policosanol (20 mg daily), the blood-thinner aspirin (100 mg daily), and policosanol and aspirin combined at these same doses. The results again showed that policosanol substantially reduced the ability of blood platelets to stick together, and that the combined therapy exhibited additive effects. Based on these findings, one should not combine heparin and policosanol except under medical supervision.
Vitamin C
Effect: Possible Harmful Interaction
Test-tube studies suggest that high amounts of vitamin C may reduce the blood-thinning effect of heparin. However, it is unclear whether the interaction is significant enough to make a practical difference.
White Willow
Effect: Possible Harmful Interaction
The herb white willow (Salix alba), also known as willow bark, is used to treat pain and fever. White willow contains a substance that the body converts into a salicylate similar to aspirin. Since combining aspirin with heparin increases the risk of abnormal bleeding, it would not be advisable to combine white willow with heparin.
Other Herbs and Supplements
Effect: Possible Harmful Interaction
Based on their known effects or constituents, the following herbs and supplements might not be safe to combine with heparin, though this has not been proven: bromelain (in the fruit and stem of pineapple, Ananas comosus), papaya (Carica papaya), chamomile (Matricaria recutita), Coleus forskohlii, danshen (Salvia miltiorrhiza), devil’s claw (Harpagophytum procumbens), dong quai (Angelica sinensis), feverfew (Tanacetum parthenium), ginger (Zingiber officinale), ginseng, horse chestnut (Aesculus hippocastanum), red clover (Trifolium pratense), reishi (Ganoderma lucidum), mesoglycan, fish oil, OPCs (oligomeric proanthocyanidins), motherwort (Leonurus cardiaca), and vitamin E.
Vitamin D
Effect: Supplementation Possibly Helpful
High doses or long-term use of heparin may interfere with the body's proper handling of vitamin D. Because vitamin D is needed for calcium absorption and utilization, this may, in turn, lead to bone loss and osteoporosis. Additionally, heparin may directly interfere with bone formation. This interaction is of particular concern during pregnancy, a period of greater calcium demand and diminished levels of a hormone that pushes calcium into bones. There have been several reports of fractured and collapsed vertebrae in pregnant women on heparin therapy. Supplementary calcium and vitamin D may help prevent heparin-induced osteoporosis. It might also be advisable to check one’s bone density during long-term heparin therapy.
Other Interactions
It is crucial to note that heparin can interact with prescription medications as well. Patients taking heparin should avoid taking additional anticoagulant drugs, as these can greatly increase the risk of bleeding, as can antiplatelet drugs. Non-steroidal Anti-inflammatory Drugs (NSAIDs) can irritate the stomach and increase the risk of bleeding when taken with heparin. Patients are advised to avoid certain antibiotics and antidepressants when taking heparin.
Bibliography
Abdel Fattah, W., and T. Hammad. "Chondroitin Sulfate and Glucosamine: A Review of Their Safety Profile." Journal of the American Nutraceutical Association, vol. 3, 2001, pp. 16-23.
Arruzazabala, M. L., et al. "Effect of Policosanol on Platelet Aggregation in Type II Hypercholesterolemic Patients." International Journal of Tissue Reactions, vol. 20, 1998, pp. 119-24.
"Heparin (Intravenous Route, Subcutaneous Route) Precautions." Mayo Clinic, 1 Sept. 2024, www.mayoclinic.org/drugs-supplements/heparin-intravenous-route-subcutaneous-route/precautions/drg-20068726. Accessed 23 Sept. 2024.
Rosenblatt, M., and J. Mindel. "Spontaneous Hyphema Associated with Ingestion of Ginkgo biloba Extract." New England Journal of Medicine, vol. 336, 1997, p. 1108.
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