Complementary/Alternative Medicine: This monograph describes a natural or herbal product that is not subject to FDA guidelines for medicines. Patients and clinicians are advised to read package labels carefully to ensure safe and efficacious use.

• PO: Hypertension, hyperlipidemia, cardiovascular disease prevention, colorectal and gastric cancer prevention
• Topical: Dermal fungal infections including tinea corporis, cruris, and pedis.

Contraindicated in:

• Bleeding disorders. Discontinue use 1–2 wk prior to surgery.

Use Cautiously in:

• Diabetes, gastrointestinal infection or inflammation.

CNS: dizziness.

GI: bad breath, diarrhea, flatulence, Irritation of the mouth, esophagus, and stomach, nausea, vomiting.

Derm: Contact dermatitis and other allergic reactions (asthma, rash, anaphylaxis [rare]), Diaphoresis.

Hemat: Chronic use or excessive dose may lead to ↓ hemoglobin production and lysis of RBCs, platelet dysfunction, prolonged bleeding time.
Misc: body odor.

Natural-Drug Products:

• Use of garlic with anticoagulants, antiplatelet agents, and thrombolytics may ↑ risk of bleeding.
• May ↓ the effectiveness of contraceptive drugs and cyclosporine.
• May ↓ plasma concentrations of saquinavir, nevirapine, delavirdine, and efavirenz.
• May ↓ isoniazid levels by 65%.

Natural-Natural Products:

• Herbs with anticoagulant or antiplatelet properties may increase bleeding risk when combined with garlic, including: angelica, anise, asafoetida, bogbean, boldo, capsicum, celery, chamomile, clove, danshen, dong quai, fenugreek, feverfew, ginger, ginkgo, Panax ginseng, horse chestnut, horseradish, licorice, meadowsweet, papain, passionflower, poplar, prickly ash, onion, quassia, red clover, , wild carrot, wild lettuce, willow, and others.

• Capsules: ^OTC;
• Tablets: ^OTC;
• Topical cream: ;
• Topical gel: ;
• Fresh garlic: ^OTC;

• PO (Adults): 200–400 mg tid of standardized garlic powder extract with 1.3% allin. Fresh garlic: 1–7 cloves per day. One clove contains approximately 4 g of garlic.
• Topical (Adults): Tinea infections: 0.4% cream, 0.6% gel, or 1% gel applied bid x 7 days.

Alli sativa bulbus, Allium sativum

• May have HMG-CoA inhibitor properties in lowering cholesterol, but less effectively than statin drugs; vasodilatory and antiplatelet properties.

• Decreased cholesterol levels.
• Decreased platelet aggregation.

Therapeutic Classification: lipid-lowering agents

Absorption: Garlic oil is well absorbed.

Distribution: Unknown.

Metabolism/Excretion: Kidney and lungs.

Half-life: Unknown.

• Instruct patients about the need to follow a healthy diet (low in fat and high in vegetables and fruits) in conjunction with garlic. Other lipid-reducing strategies, such as exercise and smoking cessation, should also be employed.
• Inform patients that there are other more effective agents for lipid reduction available.
• Caution patients about the potential for bleeding and not to take this herbal remedy without notifying their health care provider if they are taking other medications. Instruct patients undergoing elective surgery to stop using garlic 2 wk prior to surgery and to notify the surgeon that they are taking garlic in the event of emergent surgery.
• Notify patients that allergies may occur and to discontinue use if symptoms develop.
• Emphasize the need for follow-up exams with a health care professional to assess effectiveness of the regimen.

GAR-lik