Heparin

Heparin is a natural product, available by prescription, which is used as an anticoagulant (slows the rate of blood clot formation). Blood clots can cause severe and life-threatening problems. Heparin is used to prevent formation of blood clots (after surgery and in other settings) and in circumstances to help dissolve blood clots already formed (deep vein thrombosis, pulmonary embolism, and other situations involving excessive blood clotting).

Safetychecker Summary for Heparin
(for details about the summarized interactions, read the full article)

Beneficial May be Beneficial: Depletion or interference—The medication may deplete or interfere with the absorption or function of the nutrient. Taking these nutrients may help replenish them.

Vitamin D
Avoid Avoid: Adverse interaction—Avoid these supplements when taking this medication because taking them together may cause undesirable or dangerous results.

Dong quai*

Fenugreek*

Ginger*

Ginkgo biloba *

Horse chestnut*

Red clover*

Digitalis*

Reishi

Sweet clover*

Sweet woodruff*
Check Check: Other—Before taking any of these supplements or eating any of these foods with your medication, read this article in full for details.

Potassium
Side effect reduction/prevention

None known
Supportive interaction

None known
Reduced drug absorption/bioavailability

None known

An asterisk (*) next to an item in the summary indicates that the interaction is supported only by weak, fragmentary, and/or contradictory scientific evidence.

Interactions with Dietary Supplements

Potassium
Heparin therapy may cause hyperkalemia (abnormally high potassium levels).1 2 Potassium supplements, potassium-containing salt substitutes (No Salt®, Morton Salt Substitute®, and others), and even high-potassium foods (primarily fruit) should be avoided by persons on heparin therapy, unless directed otherwise by their doctor.

Vitamin D
Heparin may interfere with activation of vitamin D in the body.3 Osteoporosis (thinning of the bone) has been reported in patients who received high amounts of heparin for several months.4 Osteopenia (decreased bone density) has been reported in women who received heparin therapy during pregnancy.5 6

Interactions with Herbs

Digitalis (Digitalis purpurea)
Digitalis refers to a group of plants commonly called foxglove, which contains chemicals related to the drug digoxin. Digitalis may interfere with the anticoagulant action of heparin, reducing its action.7 Digitalis should only be used under the direct supervision of a doctor trained in its use.

Ginger
Ginger has been shown to reduce platelet stickiness in test tubes. Although there are no reports of interactions with anticoagulant drugs, people should consult a healthcare professional if they are taking an anticoagulant and wish to use ginger.8

Ginkgo biloba
Ginkgo extracts may reduce the ability of platelets to stick together, possibly increasing the tendency toward bleeding.9 Standardized extracts of ginkgo have been associated with two cases of spontaneous bleeding, although the ginkgo extracts were not definitively shown to be the cause of the problem.10 11 People taking heparin should consult with a physician knowledgeable about botanical medicines if they are considering taking ginkgo.

Herbs containing coumarin-derivatives
Although there are no specific studies demonstrating interactions with anticoagulants, the following herbs contain coumarin-like substances that may interact with heparin and could conceivably cause bleeding.12 These herbs include dong quai, fenugreek, horse chestnut, red clover, sweet clover, and sweet woodruff. People should consult a healthcare professional if they’re taking an anticoagulant and wish to use one of these herbs.

Reishi (Ganoderma lucidum)
As it may increase bleeding time, reishi is not recommended for those taking anticoagulant (blood-thinning) medications.13

Interactions with Foods and Other Compounds

Alcohol
Alcohol consumption during heparin therapy may increase the risk of serious bleeding.14 It is important for people receiving heparin to avoid alcohol during the entire course of heparin therapy.

References:

1. Threlkeld DS, ed. Blood Modifiers, Anticoagulants, Heparin. In Facts and Comparisons Drug Information. St. Louis, MO: Facts and Comparisons, Jun 1997, 87a–7f.

2. Perazella MA. Drug-induced hyperkalemia: Old culprits and new offenders. Am J Med 2000;109:307–14 [review].

3. Aarskog D, Aksens L, Markestad TK, et al. Heparin induced inhibition of 1,25-dihydroxyvitamin D formation. Am J Obstet Gynecol 1984;148:1141–2.

4. Majerus PW, Broze GJ Jr, Miletich JP, Tollefsen DM. Anticoagulant, thrombolytic, and antiplatelet drugs. In Goodman and Gilman’s The Pharmacological Basis of Therapeutics, 9th ed. New York: McGraw-Hill 1996, 1346.

5. Wise PH, Hall AS. Heparin induced osteopenia in pregnancy. BMJ 1980;281:110–1.

6. Haram K, Hervig T, Thordarson H, Aksnes L. Osteopenia caused by heparin treatment in pregnancy. Acta Obstet Gynecol Scand 1993;72:674–5.

7. Threlkeld DS, ed. Blood Modifiers, Anticoagulants, Heparin. In Facts and Comparisons Drug Information. St. Louis, MO: Facts and Comparisons, Jun 1997, 87a–7f.

8. Newall CA, Anderson LA, Phillipson JD. Herbal Medicines: A Guide for Health-Care Professionals. London: The Pharmaceutical Press, 1996, 135–7.

9. Kleijnen J, Knipschild P. Ginkgo biloba. Lancet 1992;340:1136–9.

10. Rosenblatt M, Mindel J. Spontaneous hyphema associated with ingestion of Ginkgo biloba in whom bleeding occurred after the addition of ginkgo.

11. Mathews MK. Association of Ginkgo biloba with intracerebral hemorrhage. Neurology 1998;50:1934.

12. Miller LG, Murray WJ, eds. Herbal Medicinals: A Clinician’s Guide. New York: Pharmaceutical Products Press, 1999, 313–5.

13. Brinker F. Herb Contraindications and Drug Interactions. Sandy, OR: Eclectic Medical Publications, 1998,166–9.

14. Holt GA. Food & Drug Interactions. Chicago: Precept Press, 1998, 127.