HERBAL MEDICINES OR DIETARY SUPPLEMENTS AND WARFARIN AND OTHER ORAL ANTICOAGULANTS - GARLIC

Two patients taking warfarin developed increased INRs after the addition of garlic
capsules. One patient developed haematuria. However, a controlled study suggests no
interaction occurs.
This interaction seems rare, but bear it in mind in case of unexpected bleeding. It is
worth noting that there have been cases of spontaneous bleeding attributed to
garlic alone.