Aged Garlic Extract and Warfarin

Aged garlic extract (AGE) has been shown to be useful in many areas of health maintenance, including cardiovasular health.1 The American Society for Nutrition's March 2006 issue evaluated the influence of garlic on patient's INR test results.2

Garlic (Allium sativum) is thought to provide several cardiovascular benefits, such as blood pressure lowering, serum lipid lowering, and antithrombotic activity.3, 4 You should use garlic with extreme care as additional monitoring may be required and warfarin dosage adjustments may be necessary.5

However, regular ingestion of food products containing small amounts of garlic should not pose a problem. More frequent INR testing may help you and doctor identify drug-garlic interactions more quickly than testing less often

AGE is available in liquid or pill form and can be found at most healthfood stores. As always, please speak with your doctor before using any new products or adjusting your diet.  

  1. Matsuura H. Saponins in garlic as modifiers of the risk of cardiovascular disease. J Nutr. 2001;131:1000S–5S.
  2. Hebel SK, ed. The review of natural products. St. Louis: Facts and Comparisons; 1999.
  3. O’Hara M, Kiefer D, Farrell K et al. A review of 12 commonly used medicinal herbs. Arch Fam Med. 1998; 7:523-36.
  4. Center for Medicare and Medicaid Services. (2001). Decision Memo for Prothrombin Time (INR) Monitor for Home Anticoagulation Management (CAG-00087C) [Memorandum]. Baltimore, MD.