Garlic
Allium sativum
T Traditional useGarlic powder is traditionally used to help prevent hardening of the arteries, and garlic extract to relieve symptoms of the common cold.
Image: Herbadex Botanik Stüdyosu · Özel Üretim
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At a glance
The EMA classes garlic preparations as a traditional herbal medicine for two uses: powdered garlic as an aid in preventing atherosclerosis (hardening of the arteries), and dry extract to relieve common cold symptoms. Because it can prolong bleeding, people on blood thinners and before surgery need care.
Updated: October 15, 2026
✓ This herb record is backed by official European Medicines Agency (EMA HMPC) herbal monographs.
What is it used for?
T Traditional use
Traditional use: Based on at least 30 years of documented traditional use rather than clinical trials.
How do we rate evidence levels? →Powdered garlic preparations are traditionally used as an aid in preventing atherosclerosis. [1]
T Traditional use
Traditional use: Based on at least 30 years of documented traditional use rather than clinical trials.
How do we rate evidence levels? →Dry extract is traditionally used to relieve symptoms of the common cold. [1]
How is it used?
Food
Adults take 300–750 mg of a powdered garlic preparation per dose.
Amount: 900–1380 mg a day in 3–5 doses
Duration limit: No limit on duration
[1]Food
For a cold, use a ready-made product with dry extract as labelled (e.g. 100–200 mg).
Amount: 1–2 times daily
Duration limit: See a doctor if no better within 1 week
[1]Safety & interactions
Minimum age: 12 years
- Stop 7 days before surgery because of the bleeding risk.
- Atherosclerosis use not recommended under 18; cold use not recommended under 12.
- Not recommended in pregnancy or breastfeeding because safety has not been shown.
- The assessment covers garlic preparations used as medicine, not garlic in food.
Drug interactions
| Medicine / substance | Effect | Severity |
|---|---|---|
| Anticoagulants and antiplatelet medicines (e.g. warfarin, clopidogrel) | May prolong bleeding time; use with care and with your doctor's knowledge. [1] | Moderate |
| Saquinavir/ritonavir (HIV medicines) | May lower drug levels and cause loss of effect; must not be used together. [1] | Major |
Side effects
- Breath and body odour, abdominal pain, bloating, wind, fullness
- Allergic reactions such as contact dermatitis, runny nose or wheezing, sometimes severe
- Headache, dizziness, heavy sweating
- Bleeding
⚕ When to see a doctor
- If high fever, shortness of breath or purulent/bloody phlegm develops
- If symptoms do not improve within 1–2 weeks or worsen
- If severe abdominal pain, jaundice, rash or allergic reaction occurs
Did you know?
Per the EMA, garlic preparations should be stopped 7 days before surgery. [1]
Frequently asked questions
Is garlic good for cholesterol or the arteries?
The EMA accepts powdered garlic as a traditional aid in preventing atherosclerosis. It does not replace cholesterol medicines.
Can I take garlic with blood thinners?
It may prolong bleeding, so people on warfarin or antiplatelet medicines should take care and ask a doctor.
Should I stop garlic before surgery?
Yes. The EMA advises stopping garlic preparations 7 days before surgery because of the bleeding risk.
Does this cover garlic in food?
No. The assessment covers powdered and extract preparations used as medicine.
Sources
- European Union herbal monograph on Allium sativum L., bulbusEMA HMPC · 2017
Cite This Page
Garlic (Allium sativum). Herbadex — Doğal Şifa Rehberi (2026). https://herbadex.com/en/herb/garlic/
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