http://umm.edu/health/medical/altmed/herb/garlic
Garlic may interact with a number of medications, including the ones listed below. To be safe, if you take an prescription medicines, ask your doctor before taking garlic supplements.
Birth control pills -- Garlic may make birth control pills less effective.
Cyclosporine -- Garlic may interact with cyclosporine, a medication taken after organ transplant, and make it less effective.
Blood-thinning medications -- Garlic may make the actions of these medications stronger, increasing the risk of bleeding. Blood-thinners include warfarin (Coumadin), clopidogrel (Plavix), and aspirin.
Medications for HIV/AIDS -- Garlic may lower blood levels of protease inhibitors, medications used to treat people with HIV. Protease inhibitors include:
Amprenavir (Agenerase)
Fosamprenavir (Lexiva)
Indinavir (Crixivan)
Nelfinavir (Viracept)
Ritonavir (Norvir)
Saquinavir (Fortovase)
Nonsteroidal anti-inflammatory drugs (NSAIDs) -- Both NSAIDs and garlic may increase the risk of bleeding. NSAIDs include ibuprofen (Advil, Motrin) and naproxen (Aleve) as well as prescription medications.
Supporting Research
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