Garlic Interactions Overview

Additional Details

Is Garlic Safe? Are There Any Warnings?

Garlic is generally safe for oral use when used appropriately. Clinical studies lasting up to 7 years have shown no significant toxicity. Topical use of garlic-containing products like gels, extracts, pastes, and mouthwashes is also considered safe for up to 3 months. However, raw garlic can cause severe skin irritation when applied topically. When used orally in normal food amounts, garlic is likely safe during pregnancy, but medicinal amounts should be avoided. There is no evidence of garlic adversely affecting pregnancy, and daily use of 800 mg during the third trimester has not shown any adverse effects. The safety of topical garlic during pregnancy is uncertain.

How Is Garlic Thought To Work?

Garlic contains various compounds, including allicin, ajoene, and alliin. When the garlic bulb is crushed or cut, the alliin is converted to allicin by an enzyme called alliinase. Allicin is responsible for many of garlic's effects. Other sulfur compounds and volatile constituents in garlic, such as diallyldisulfide and dimethyltrisulfide, may also contribute to its biological activity. Garlic extracts and oils can be standardized to ensure consistent levels of these active compounds. The age and preparation method of garlic can affect the content and potency of these constituents.

Pharmacokinetics

After ingestion or topical application, garlic compounds are well absorbed through mucous membranes and skin. Allicin and other garlic constituents are metabolized in the liver and kidneys. Metabolites of garlic include allicin, allyl-mercaptan, and diallyl disulfide. Garlic is primarily excreted in urine and feces. The elimination half-life of one garlic constituent, N-acetyl-S-allyl-L-cysteine, is approximately six hours. The pharmacokinetics of garlic follow certain patterns of absorption, metabolism, and excretion.

Interaction Overview (See Below For Full List)

Garlic may interact with certain medications and supplements, including anticoagulants (blood thinners) and antiplatelet drugs. It may increase the risk of bleeding when used with these medications. It's important to consult a healthcare professional if you're taking any medications or have underlying health conditions before using garlic supplements.

Common Side Effects To Watch For

When taken orally, garlic may cause abdominal pain, body odor, flatulence, malodorous breath, and nausea. Some individuals may experience allergic reactions. Topical use of fresh garlic can lead to burns and dermatitis. These side effects are generally rare and not severe, but it's important to be aware of them.

Are Supplements Standardized?

Yes, many garlic products, including powder, oil, and extract, can be standardized to ensure consistent levels of active compounds. The standardization is often based on the content of allicin, which is a key compound in garlic. Different formulations and brands may have varying concentrations of allicin, and enteric coating can be used to protect the active constituents from stomach acid.

Drugs that interact with Garlic