Herb & supplement monograph

Garlic Drug Interactions, Uses, Effectiveness, Safety & More

Medically reviewed by ·Updated July 2026
What is this page for?

First and foremost: how Garlic interacts with medications. The heart of this page is the interaction list — every drug Garlic is known to interact with, and how serious each one is.

But these pages have grown well beyond that into a full monograph — what Garlic is, what people use it for and how strong the evidence is, its safety and side effects, and answers to the questions we’re asked most — written and reviewed by the clinical staff at HelloPharmacist. It’s educational information from our licensed clinical databases, not medical advice, and we don’t sell or endorse products. Our editorial policy

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Garlic Drug Interactions: The Bottom Line

From the HelloPharmacist Editorial Team · Updated July 2026

Based on the available evidence, the overall risk of a clinically significant Garlic drug interaction appears low for most people. None of garlic's listed interactions are rated major, and nearly all rest on lab, animal, or limited human evidence rather than well-controlled human studies.

Interactions deserving the most attention

The pairings that deserve the most care involve bleeding, blood sugar, and drug levels. Garlic has antiplatelet activity and may add to the effect of warfarin and other blood thinners, and human research shows it can lower blood glucose, which matters for people taking diabetes medications. Human studies also suggest allicin-containing garlic products may reduce levels of HIV protease inhibitors such as saquinavir, and a case report links a garlic supplement to raised levels of the transplant drug tacrolimus.

What the rest of the list means

The long list of interacting medications mostly reflects one prediction: garlic may affect enzymes the body uses to clear many different drugs. Because of that, hundreds of medications are flagged even though most of these pairings are theoretical, and some predicted effects have not held up when tested in people. A flagged combination is a reason for awareness, not proof of harm.

Check your medications against Garlic

Based on HelloPharmacist’s Garlic interaction data and reviewed under our editorial standards.

Interaction report

Drugs that interact with Garlic

989 medications have a known interaction with Garlic, graded by severity. Select any drug for the full evidence-based detail.

2,830 drugs
Ado-trastuzumab EmtansineKadcyla
Moderate Cytochrome P450 3a4 (cyp3a4) Substrates

Theoretically, garlic products containing allicin might induce intestinal CYP3A4 and inhibit hepatic CYP3A4.

Read the full Garlic + Ado-trastuzumab Emtansine interaction Ado-trastuzumab Emtansine drug page: uses, dosage & side effects
AbciximabReoPro
Moderate Anticoagulant/antiplatelet Drugs

Garlic may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.

Read the full Garlic + Abciximab interaction
AbemaciclibVerzenio
Moderate Cytochrome P450 3a4 (cyp3a4) Substrates

Theoretically, garlic products containing allicin might induce intestinal CYP3A4 and inhibit hepatic CYP3A4.

Read the full Garlic + Abemaciclib interaction Abemaciclib drug page: uses, dosage & side effects
Abiraterone
Moderate Cytochrome P450 3a4 (cyp3a4) Substrates

Theoretically, garlic products containing allicin might induce intestinal CYP3A4 and inhibit hepatic CYP3A4.

Read the full Garlic + Abiraterone interaction Abiraterone drug page: uses, dosage & side effects
Abiraterone AcetateYonsa, Zytiga
Moderate Cytochrome P450 3a4 (cyp3a4) Substrates

Theoretically, garlic products containing allicin might induce intestinal CYP3A4 and inhibit hepatic CYP3A4.

Read the full Garlic + Abiraterone Acetate interaction Abiraterone Acetate drug page: uses, dosage & side effects
AbrocitinibCibinqo
Moderate Anticoagulant/antiplatelet Drugs

Garlic may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.

Read the full Garlic + Abrocitinib interaction Abrocitinib drug page: uses, dosage & side effects
AcalabrutinibCalquence
Moderate Cytochrome P450 3a4 (cyp3a4) Substrates

Theoretically, garlic products containing allicin might induce intestinal CYP3A4 and inhibit hepatic CYP3A4.

Read the full Garlic + Acalabrutinib interaction Acalabrutinib drug page: uses, dosage & side effects
AcarboseGlucobay, Prandase, Precose
Moderate Antidiabetes Drugs

Theoretically, taking garlic with antidiabetes drugs might increase the risk of hypoglycemia.

Read the full Garlic + Acarbose interaction Acarbose drug page: uses, dosage & side effects
AcebutololRhotral, Sectral
Moderate Antihypertensive Drugs

Theoretically, taking garlic with antihypertensive drugs might increase the risk of hypotension.

Read the full Garlic + Acebutolol interaction Acebutolol drug page: uses, dosage & side effects
AcenocoumarolSintrom
Moderate Anticoagulant/antiplatelet Drugs

Garlic may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.

Read the full Garlic + Acenocoumarol interaction
AcetaminophenChildren's Tylenol, Children's Tylenol Meltaways, Tylenol, Tylenol Ex Strength
Moderate Cytochrome P450 2e1 (cyp2e1) Substrates

Garlic might increase levels of drugs metabolized by CYP2E1.

Read the full Garlic + Acetaminophen interaction Acetaminophen drug page: uses, dosage & side effects
Acetaminophen, AspirinGemnisyn
Moderate Cytochrome P450 2e1 (cyp2e1) Substrates

Garlic might increase levels of drugs metabolized by CYP2E1.

Read the full Garlic + Acetaminophen, Aspirin interaction
Acetaminophen, Aspirin, CaffeineExcedrin, Excedrin Extra Strength, Excedrin Migraine
Moderate Anticoagulant/antiplatelet Drugs

Garlic may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.

Read the full Garlic + Acetaminophen, Aspirin, Caffeine interaction
Acetaminophen, Brompheniramine, PhenylpropanolamineDimetapp Cold and Flu
Moderate Cytochrome P450 2e1 (cyp2e1) Substrates

Garlic might increase levels of drugs metabolized by CYP2E1.

Read the full Garlic + Acetaminophen, Brompheniramine, Phenylpropanolamine interaction
Acetaminophen, ButalbitalAxocet, Bancap, Bucet, Butex Forte, Esgic CF, Orbivan CF +5 more
Moderate Cytochrome P450 2e1 (cyp2e1) Substrates

Garlic might increase levels of drugs metabolized by CYP2E1.

Read the full Garlic + Acetaminophen, Butalbital interaction
Acetaminophen, Butalbital, CaffeineEsgic, Esgic Plus, Fiogesic, Fioricet, Repan, Tecnal +1 more
Moderate Cytochrome P450 2e1 (cyp2e1) Substrates

Garlic might increase levels of drugs metabolized by CYP2E1.

Read the full Garlic + Acetaminophen, Butalbital, Caffeine interaction Acetaminophen, Butalbital, Caffeine drug page: uses, dosage & side effects
Acetaminophen, Butalbital, Caffeine, CodeineEsgic with Codeine, Fioricet w/ Codeine
Moderate Cytochrome P450 3a4 (cyp3a4) Substrates

Theoretically, garlic products containing allicin might induce intestinal CYP3A4 and inhibit hepatic CYP3A4.

Read the full Garlic + Acetaminophen, Butalbital, Caffeine, Codeine interaction
Acetaminophen, Butalbital, CodeineBancap w/ Codeine
Moderate Cytochrome P450 2e1 (cyp2e1) Substrates

Garlic might increase levels of drugs metabolized by CYP2E1.

Read the full Garlic + Acetaminophen, Butalbital, Codeine interaction
Acetaminophen, Butalbital, Codeine PhosphatePhrenilin #3
Moderate Cytochrome P450 2e1 (cyp2e1) Substrates

Garlic might increase levels of drugs metabolized by CYP2E1.

Read the full Garlic + Acetaminophen, Butalbital, Codeine Phosphate interaction
Acetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, PhenylephrineHycomine Compound
Moderate Cytochrome P450 2e1 (cyp2e1) Substrates

Garlic might increase levels of drugs metabolized by CYP2E1.

Read the full Garlic + Acetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, Phenylephrine interaction
Acetaminophen, Caffeine, CodeineGesic C15, Gesic C30, Gesic C8, Lenoltec 1, Lenoltec 2, Lenoltec 3 +1 more
Moderate Cytochrome P450 3a4 (cyp3a4) Substrates

Theoretically, garlic products containing allicin might induce intestinal CYP3A4 and inhibit hepatic CYP3A4.

Read the full Garlic + Acetaminophen, Caffeine, Codeine interaction
Acetaminophen, Caffeine, Codeine, SalicylamideCodalan No.1, Codalan No.2, Codalan No.3
Moderate Cytochrome P450 2e1 (cyp2e1) Substrates

Garlic might increase levels of drugs metabolized by CYP2E1.

Read the full Garlic + Acetaminophen, Caffeine, Codeine, Salicylamide interaction
Acetaminophen, Caffeine, DihydrocodeineDHC Plus, Panlor DC, Panlor SS
Moderate Cytochrome P450 3a4 (cyp3a4) Substrates

Theoretically, garlic products containing allicin might induce intestinal CYP3A4 and inhibit hepatic CYP3A4.

Read the full Garlic + Acetaminophen, Caffeine, Dihydrocodeine interaction
Acetaminophen, Caffeine, IsomethepteneMigralam
Moderate Cytochrome P450 2e1 (cyp2e1) Substrates

Garlic might increase levels of drugs metabolized by CYP2E1.

Read the full Garlic + Acetaminophen, Caffeine, Isometheptene interaction
Acetaminophen, Caffeine, PyrilamineMidol Max Strength Menstrual
Moderate Cytochrome P450 3a4 (cyp3a4) Substrates

Theoretically, garlic products containing allicin might induce intestinal CYP3A4 and inhibit hepatic CYP3A4.

Read the full Garlic + Acetaminophen, Caffeine, Pyrilamine interaction
Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HbrVicks Formula 44M Cough, Cold & Flu Relief
Moderate Cytochrome P450 2e1 (cyp2e1) Substrates

Garlic might increase levels of drugs metabolized by CYP2E1.

Read the full Garlic + Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan Hbr interaction
Acetaminophen, Chlorpheniramine, Codeine, PhenylephrineColrex
Moderate Cytochrome P450 2e1 (cyp2e1) Substrates

Garlic might increase levels of drugs metabolized by CYP2E1.

Read the full Garlic + Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine interaction
Acetaminophen, Chlorpheniramine, DextromethorphanCoricidin II Extra Strength Cold and Flu
Moderate Cytochrome P450 3a4 (cyp3a4) Substrates

Theoretically, garlic products containing allicin might induce intestinal CYP3A4 and inhibit hepatic CYP3A4.

Read the full Garlic + Acetaminophen, Chlorpheniramine, Dextromethorphan interaction
Acetaminophen, Chlorpheniramine, Dextromethorphan HydrobromideCoricidin HBP Maximum Strength Flu
Moderate Cytochrome P450 2e1 (cyp2e1) Substrates

Garlic might increase levels of drugs metabolized by CYP2E1.

Read the full Garlic + Acetaminophen, Chlorpheniramine, Dextromethorphan Hydrobromide interaction
Acetaminophen, Chlorpheniramine, Dextromethorphan, PhenylpropanolamineMulti Symptom Cold Relief
Moderate Cytochrome P450 3a4 (cyp3a4) Substrates

Theoretically, garlic products containing allicin might induce intestinal CYP3A4 and inhibit hepatic CYP3A4.

Read the full Garlic + Acetaminophen, Chlorpheniramine, Dextromethorphan, Phenylpropanolamine interaction
Read The List Like a Pharmacist

What Severity, Likelihood & Evidence Mean

Severity — How Serious It Can Be

  • Major. Clinically significant; generally best avoided, or used only under direct professional supervision.
  • Moderate. May need monitoring, a dose adjustment, or separating the times you take each one.
  • Minor. Generally not clinically significant, but still worth noting and mentioning to your pharmacist.
  • No known interaction. Checked against our sources with nothing documented — not the same as proven safety.

Likelihood — How Well It’s Documented

  • Likely. Well-controlled human studies have demonstrated the likely existence of this interaction
  • Probable. Interaction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • Possible. Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists
  • Unlikely. Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans.

Where This Data Comes From

  • Interaction records are evidence-graded and sourced from the Natural Medicines database (TRC Healthcare), the same reference used by pharmacists and hospitals.
  • Each drug listed above links to the full report for that exact Garlic combination — clinical detail, likelihood, evidence level, and citations.
  • Content is reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.
The big picture

The kinds of drugs Garlic affects

Every type of medication (drug category) Garlic is known to interact with. Open any category for the detail — or search your exact drug in the checker above.

All 12 drug categories Garlic interacts with
Anticoagulant/antiplatelet DrugsAntidiabetes DrugsAntihypertensive DrugsAtazanavir (reyataz)Cytochrome P450 2e1 (cyp2e1) SubstratesCytochrome P450 3a4 (cyp3a4) SubstratesIsoniazidProtease Inhibitors (pis)Saquinavir (fortovase, Invirase)Sofosbuvir (sovaldi)Tacrolimus (prograf)Warfarin (coumadin)
Anticoagulant/Antiplatelet Drugs

Garlic may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Raw garlic and a variety of garlic extracts have antiplatelet activity and can increase prothrombin time.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, taking garlic with antidiabetes drugs might increase the risk of hypoglycemia.
Clinical research suggests that garlic and garlic extract lower blood glucose levels in healthy and diabetic individuals.

Likelihood Possible Evidence B
Antihypertensive Drugs

Theoretically, taking garlic with antihypertensive drugs might increase the risk of hypotension.
In human research, both garlic and garlic extracts have blood pressure-lowering effects.

Likelihood Possible Evidence D
Atazanavir (Reyataz)

Theoretically, garlic might decrease levels and effects of atazanavir.
In a case report, a patient consuming six stir-fried garlic cloves three times weekly developed suboptimal atazanavir levels and increases in HIV viral load. While the exact cause of this interaction is unclear, there is speculation that garlic might decrease the intestinal absorption of atazanavir or increase its metabolism by inducing cytochrome P450 3A4 (CYP3A4). Until more is known, advise patients not to consume large amounts of garlic while taking atazanavir.

Likelihood Possible Evidence D
Cytochrome P450 2E1 (Cyp2E1) Substrates

Garlic might increase levels of drugs metabolized by CYP2E1.
Clinical research suggests garlic oil can inhibit the activity of CYP2E1 by 39%. Use garlic oil cautiously in patients taking drugs metabolized by these enzymes.

Likelihood Probable Evidence B
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, garlic products containing allicin might induce intestinal CYP3A4 and inhibit hepatic CYP3A4. This may increase or decrease levels of drugs metabolized by CYP3A4.
Some human research suggests that garlic may induce INTESTINAL CYP3A4, reducing levels of drugs metabolized by this enzyme. This is primarily based on a study showing that taking a specific allicin-containing garlic product (GarliPure Maximum Allicin Formula, Natrol Inc.) twice daily for 3 days reduces saquinavir levels by approximately 50%. It is speculated that the allicin constituent induced CYP3A4 in the gut mucosa. Another study shows that giving docetaxel intravenously, bypassing the CYP3A4 enzymes in the gut mucosa, along with the same specific garlic product for 12 consecutive days, does not affect docetaxel levels. Conversely, there is concern that garlic may inhibit HEPATIC CYP3A4. In a single case report, increased tacrolimus levels and liver injury occurred in a liver transplant patient after taking a specific garlic supplement (Garlicin Cardio, Nature's Way) at up to three times the manufacturer recommended dose for 7 days. Several other studies have evaluated the impact of other garlic formulations on CYP3A4 substrates and have found no effect. Most of the products in these studies provided little or no allicin.

Likelihood Possible Evidence B
Isoniazid

Theoretically, garlic might decrease levels of isoniazid.
Animal research suggests that an aqueous extract of garlic reduces isoniazid levels by about 65%. Garlic reduced the maximum concentration (Cmax) and area under the curve (AUC), but not the half-life, of isoniazid. This suggests that garlic extract might inhibit isoniazid absorption across the intestinal mucosa; however, the exact mechanism of this potential interaction is not known.

Likelihood Possible Evidence D
Protease Inhibitors (Pis)

Theoretically, garlic products containing allicin might decrease levels of PIs.
Protease inhibitors are metabolized by cytochrome P450 3A4 (CYP3A4) isoenzymes. There is concern that garlic products containing allicin might induce intestinal CYP3A4, reducing plasma levels of protease inhibitors. This is primarily based on a study showing that taking a specific garlic product (GarliPure Maximum Allicin Formula, Natrol Inc.) twice daily for 3 days reduces levels of saquinavir, a PI, by approximately 50%. It is speculated that the allicin constituent induce CYP3A4 in the gut mucosa. Several studies have evaluated the impact of other garlic formulations on CYP3A4 substrates and have found no effect. Most of the products in these studies provided little or no allicin.

Likelihood Possible Evidence B
Saquinavir (Fortovase, Invirase)

Theoretically, garlic containing allicin might decrease levels of saquinavir.
Saquinavir is a substrate of cytochrome P450 3A4 (CYP3A4) isoenzymes. There is concern that garlic products containing allicin might induce intestinal CYP3A4 and cause subtherapeutic levels of saquinavir. This is primarily based on a pharmacokinetic study showing that taking a specific garlic product (GarliPure Maximum Allicin Formula, Natrol Inc.) twice daily for 3 days reduces saquinavir levels by approximately 50%. It is speculated that the allicin constituent induces CYP3A4 in the gut mucosa. Several pharmacokinetic studies have evaluated the impact of other garlic formulations on CYP3A4 substrates and have found no effect. Most of the products in these studies provided little or no allicin. Until more is known about this potential interaction, use garlic containing allicin cautiously in patients taking saquinavir.

Likelihood Possible Evidence B
Sofosbuvir (Sovaldi)

Theoretically, taking garlic with sofosbuvir might decrease its effectiveness.
Animal research in rats shows that giving aged garlic extract 120 mg/kg orally daily for 14 days decreases the area under the concentration time curve (AUC) after a single sofosbuvir dose of 40 mg/kg by 36%, increases the clearance by 63%, and decreases the plasma concentrations at 1 and 8 hours by 35% and 58%, respectively. This interaction is hypothesized to be due to induction of intestinal P-glycoprotein expression by garlic.

Likelihood Possible Evidence D
Tacrolimus (Prograf)

Theoretically, garlic might increase levels of tacrolimus.
In one case report, a liver transplant patient taking tacrolimus experienced increased tacrolimus levels and liver injury after taking a specific garlic supplement (Garlicin Cardio, Nature's Way) at up to three times the manufacturer recommended dose for 7 days. It is speculated that garlic inhibited hepatic cytochrome P450 3A4 (CYP3A4), which increased plasma levels of tacrolimus.

Likelihood Possible Evidence B
Warfarin (Coumadin)

Theoretically, garlic might increase the risk of bleeding with warfarin.
Raw garlic and a variety of garlic extracts have antiplatelet activity and can increase prothrombin time. In addition, there is a report of two patients who experienced an increase in a previously stabilized international normalized ratio (INR) with concomitant garlic and warfarin use. However, this report has been subsequently debated due to limited clinical information. Other clinical studies have not identified an effect of garlic on INR, warfarin pharmacokinetics, or bleeding risk. More evidence is needed to determine the safety of using garlic with warfarin.

Likelihood Possible Evidence D
Monograph

Garlic: Uses, Safety & Side Effects

Medically reviewed by · Reviewed July 2026 ·
The bottom line

Garlic is a common food and supplement that may modestly help with blood pressure and cholesterol, though the evidence is mixed and effects are usually small. It is generally safe in food amounts, but concentrated supplements can cause stomach upset, breath and body odor, and a higher risk of bleeding. Talk with your pharmacist or doctor before taking garlic supplements, especially if you take other medicines.

Garlic
Scientific name
Allium sativum
Family
Amaryllidaceae
Part used
Bulb (cloves)
Common forms
Fresh cloves, powder, capsules, tablets, softgels, aged garlic extract, garlic oil
People commonly use it for
  • High blood pressure
  • High cholesterol
  • Heart health
  • Immune support and common cold
  • Antimicrobial uses

Popular and traditional uses — not proof it works. See “Uses & effectiveness” below for the evidence.

Safety at a glance
OverallUse caution

Generally safe as food, but supplements may cause stomach upset and increase bleeding risk.

PregnancyLikely Safe

When used orally in amounts commonly found in foods.

Read the full pregnancy detail
BreastfeedingLikely Safe

When used orally in amounts commonly found in foods.

Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center). Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Jump to a section

Overview

Garlic (Allium sativum) is a pungent bulb in the onion family. It is native to central Asia but is now grown all over the world. People have used it as a food and a folk remedy for thousands of years.

Besides cooking, garlic is taken as a supplement for heart and circulation health, cholesterol, and as a general immune booster. It comes in many forms, including fresh cloves, dried powder, capsules, oils, and aged garlic extract, which is made by soaking sliced garlic in alcohol over many months.

How it works

When garlic is crushed or chopped, it releases a compound called alliin, which an enzyme quickly turns into allicin. Allicin and other sulfur-containing compounds are thought to be responsible for many of garlic's effects and its strong smell.

Researchers believe these compounds may help relax blood vessels, support healthy cholesterol levels, and act against certain microbes. Garlic compounds may also affect how blood platelets clump together, which is why garlic can thin the blood slightly.

Much of this work comes from laboratory and animal studies, so it does not always translate into clear benefits in people.

Effectiveness

Does Garlic work?

Here’s what the research actually shows for each use — graded by Natural Medicines and reviewed by .

Evidence overview · 69 uses evaluated
6 Possibly effective 2 Leans ineffective 61 Insufficient evidence
How to read these evidence grades

Natural Medicines’ 7-point scale. We show each rating’s label word-for-word.

1EffectiveStrong, consistent evidence it works.
2Likely EffectiveGood evidence, though not yet conclusive.
3Possibly EffectiveSome evidence suggests a benefit.
4Possibly IneffectiveSome evidence it may not help.
5Likely IneffectiveFairly strong evidence it doesn’t help.
6IneffectiveStrong evidence it doesn’t work.
7Insufficient Reliable Evidence to RateToo little research to say either way.
Possibly Effective Atherosclerosis
Rating & evidence shown verbatim from Natural Medicines

When used alone or in combination with other ingredients, oral garlic seems to slow the progression of atherosclerosis.

Possibly Effective Diabetes
Rating & evidence shown verbatim from Natural Medicines

Most clinical research suggests that oral garlic, taken alone or in combination with metformin for at least 12 weeks, modestly reduces fasting blood glucose levels in patients with diabetes. It is unclear if garlic improves postprandial glucose levels or glycated hemoglobin (HbA1c).

Possibly Effective Endometriosis
Rating & evidence shown verbatim from Natural Medicines

Oral garlic seems to improve pain in people with endometriosis.

Possibly Effective Hypertension
Rating & evidence shown verbatim from Natural Medicines

Some clinical research suggests that oral garlic seems to modestly reduce blood pressure in hypertensive and normotensive patients.

Possibly Effective Nonalcoholic fatty liver disease (NAFLD)
Rating & evidence shown verbatim from Natural Medicines

Oral garlic seems to reduce the severity of hepatic steatosis in patients with NAFLD.

Possibly Effective Periodontitis
Rating & evidence shown verbatim from Natural Medicines

Oral aged garlic extract seems to improve some measures of gum health in people with mild to moderate periodontitis.

Possibly Ineffective Gastric cancer
Rating & evidence shown verbatim from Natural Medicines

Oral garlic does not seem to prevent gastric cancer.

Possibly Ineffective Helicobacter pylori
Rating & evidence shown verbatim from Natural Medicines

Oral garlic does not seem to be beneficial for Helicobacter pylori eradication.

Also studied for 61 conditions — evidence insufficient to rate
Insufficient Reliable Evidence To Rate Allergic rhinitis (hay fever)
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral garlic for allergic rhinitis (hay fever), there is insufficient reliable information about the clinical effects of garlic for this condition.

Insufficient Reliable Evidence To Rate Alopecia areata
Rating & evidence shown verbatim from Natural Medicines

Topical garlic may increase hair growth by a small amount.

Insufficient Reliable Evidence To Rate Asthma
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral garlic for asthma, there is insufficient reliable information about the clinical effects of garlic for this condition.

Insufficient Reliable Evidence To Rate Athletic performance
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for athletic performance.

Insufficient Reliable Evidence To Rate Benign prostatic hyperplasia (BPH)
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for BPH.

Insufficient Reliable Evidence To Rate Bladder cancer
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral garlic for bladder cancer, there is insufficient reliable information about the clinical effects of garlic for this condition.

Insufficient Reliable Evidence To Rate Breast cancer
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic prevents breast cancer.

Insufficient Reliable Evidence To Rate Bronchitis
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral garlic for bronchitis, there is insufficient reliable information about the clinical effects of garlic for this condition.

Insufficient Reliable Evidence To Rate Cardiovascular disease (CVD)
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for reducing CVD risk factors in adults with hypercholesterolemia.

Insufficient Reliable Evidence To Rate Chronic fatigue syndrome (CFS)
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral garlic for CFS, there is insufficient reliable information about the clinical effects of garlic for this condition.

Insufficient Reliable Evidence To Rate Colorectal cancer
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic prevents colorectal cancer.

Insufficient Reliable Evidence To Rate Common cold
Rating & evidence shown verbatim from Natural Medicines

Oral garlic might reduce the frequency of the common cold when used prophylactically.

Insufficient Reliable Evidence To Rate Corns
Rating & evidence shown verbatim from Natural Medicines

It is unclear if topical garlic is beneficial for corns.

Insufficient Reliable Evidence To Rate Coronary heart disease (CHD)
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for CHD.

Insufficient Reliable Evidence To Rate Coronavirus disease 2019 (COVID-19)
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for COVID-19.

Insufficient Reliable Evidence To Rate Cystic fibrosis
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for cystic fibrosis.

Insufficient Reliable Evidence To Rate Dental hypersensitivity
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral garlic for dental hypersensitivity, there is insufficient reliable information about the clinical effects of garlic for this condition.

Insufficient Reliable Evidence To Rate Denture stomatitis
Rating & evidence shown verbatim from Natural Medicines

It is unclear if topical garlic as a mouthwash is beneficial for denture stomatitis.

Insufficient Reliable Evidence To Rate Diabetic retinopathy
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for diabetic retinopathy.

Insufficient Reliable Evidence To Rate Diarrhea
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral garlic for various types of diarrhea, including travelers' diarrhea and dysentery, there is insufficient reliable information about the clinical effects of garlic for these conditions.

Insufficient Reliable Evidence To Rate Dysmenorrhea
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral garlic for dysmenorrhea, there is insufficient reliable information about the clinical effects of garlic for this condition.

Insufficient Reliable Evidence To Rate Erectile dysfunction (ED)
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for erectile dysfunction.

Insufficient Reliable Evidence To Rate Esophageal cancer
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic prevents esophageal cancer.

Insufficient Reliable Evidence To Rate Exercise-induced muscle soreness
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for exercise-induced muscle soreness.

Insufficient Reliable Evidence To Rate Familial hypercholesterolemia
Rating & evidence shown verbatim from Natural Medicines

Oral garlic does not seem to improve blood lipid levels in children with familial hypercholesterolemia.

Insufficient Reliable Evidence To Rate Fibrocystic breast disease
Rating & evidence shown verbatim from Natural Medicines

Oral garlic has only been evaluated in combination with other ingredients; its effect when used alone is unclear.

Insufficient Reliable Evidence To Rate Gastritis
Rating & evidence shown verbatim from Natural Medicines

Oral garlic has only been evaluated in combination with other ingredients; its effect when used alone is unclear.

Insufficient Reliable Evidence To Rate Gout
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral garlic for gout, there is insufficient reliable information about the clinical effects of garlic for this condition.

Insufficient Reliable Evidence To Rate Hepatitis
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for hepatitis.

Insufficient Reliable Evidence To Rate Hepatopulmonary syndrome
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for hepatopulmonary syndrome.

Insufficient Reliable Evidence To Rate Influenza
Rating & evidence shown verbatim from Natural Medicines

Oral garlic has only been evaluated in combination with other ingredients; its effect when used alone is unclear.

Insufficient Reliable Evidence To Rate Lead toxicity
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for lead toxicity.

Insufficient Reliable Evidence To Rate Lung cancer
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic prevents lung cancer.

Insufficient Reliable Evidence To Rate Metabolic syndrome
Rating & evidence shown verbatim from Natural Medicines

Meta-analyses of small studies suggest that oral garlic may improve some metabolic parameters in patients with metabolic syndrome and other metabolic disorders.

Insufficient Reliable Evidence To Rate Mosquito repellent
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial as a mosquito repellent.

Insufficient Reliable Evidence To Rate Multiple myeloma
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic prevents multiple myeloma.

Insufficient Reliable Evidence To Rate Muscle strength
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for muscle strength.

Insufficient Reliable Evidence To Rate Obesity
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for obesity.

Insufficient Reliable Evidence To Rate Onychomycosis
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using topical garlic for onychomycosis, there is insufficient reliable information about the clinical effects of garlic for this condition.

Insufficient Reliable Evidence To Rate Oropharyngeal candidiasis
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for oropharyngeal candidiasis.

Insufficient Reliable Evidence To Rate Osteoarthritis
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for osteoarthritis.

Insufficient Reliable Evidence To Rate Otitis media
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using topical garlic for otitis media, there is insufficient reliable information about the clinical effects of garlic for this condition.

Insufficient Reliable Evidence To Rate Peripheral arterial disease (PAD)
Rating & evidence shown verbatim from Natural Medicines

Oral garlic seems to improve pain-free walking distance by a small amount in patients with PAD. However, it does not seem to improve blood pressure.

Insufficient Reliable Evidence To Rate Polycystic ovary syndrome (PCOS)
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for PCOS.

Insufficient Reliable Evidence To Rate Pre-eclampsia
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic prevents pre-eclampsia during the third trimester.

Insufficient Reliable Evidence To Rate Premenstrual syndrome (PMS)
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for PMS.

Insufficient Reliable Evidence To Rate Prostate cancer
Rating & evidence shown verbatim from Natural Medicines

Observational research on the relationship between garlic intake and prostate cancer risk is conflicting. It is unclear if garlic supplements are beneficial in patients with prostate cancer.

Insufficient Reliable Evidence To Rate Rheumatoid arthritis (RA)
Rating & evidence shown verbatim from Natural Medicines

Oral garlic seems to reduce pain by a small amount in patients with RA.

Insufficient Reliable Evidence To Rate Scleroderma
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial for scleroderma.

Insufficient Reliable Evidence To Rate Stress
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral garlic for stress, there is insufficient reliable information about the clinical effects of garlic for this condition.

Insufficient Reliable Evidence To Rate Tick repellent
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral garlic is beneficial as a tick repellent.

Insufficient Reliable Evidence To Rate Tinea capitis
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using topical garlic for tinea capitis, there is insufficient reliable information about the clinical effects of garlic for this condition.

Insufficient Reliable Evidence To Rate Tinea corporis
Rating & evidence shown verbatim from Natural Medicines

It is unclear if topical garlic is beneficial for tinea corporis.

Insufficient Reliable Evidence To Rate Tinea cruris
Rating & evidence shown verbatim from Natural Medicines

It is unclear if topical garlic is beneficial for tinea cruris.

Insufficient Reliable Evidence To Rate Tinea pedis
Rating & evidence shown verbatim from Natural Medicines

It is unclear if topical garlic is beneficial for tinea pedis.

Insufficient Reliable Evidence To Rate Trichomoniasis
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral garlic for trichomoniasis, there is insufficient reliable information about the clinical effects of garlic for this condition.

Insufficient Reliable Evidence To Rate Tuberculosis
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral garlic for tuberculosis, there is insufficient reliable information about the clinical effects of garlic for this condition.

Insufficient Reliable Evidence To Rate Unstable angina
Rating & evidence shown verbatim from Natural Medicines

It is unclear if intravenous garlic is beneficial for unstable angina.

Insufficient Reliable Evidence To Rate Urinary tract infections (UTIs)
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral garlic for UTIs, there is insufficient reliable information about the clinical effects of garlic for this condition.

Insufficient Reliable Evidence To Rate Warts
Rating & evidence shown verbatim from Natural Medicines

It is unclear if topical garlic is beneficial for warts.

Insufficient Reliable Evidence To Rate Wound healing
Rating & evidence shown verbatim from Natural Medicines

It is unclear if topical garlic is beneficial for wound healing.

Source & disclaimer. Effectiveness ratings and evidence summaries are provided by Natural Medicines (Therapeutic Research Center) and shown as licensed. Where Natural Medicines hasn’t rated a use, HelloPharmacist’s pharmacists may add their own reviewed rating and evidence (each such entry is labeled). This is educational information, not medical advice — talk with your pharmacist or doctor before starting, stopping, or changing a supplement.

Safety & precautions

Garlic eaten as food is generally recognized as safe for most people. Concentrated supplements are usually well tolerated but carry a higher chance of side effects.

Because garlic may slow blood clotting, use caution if you have a bleeding disorder or are scheduled for surgery. Many clinicians suggest stopping garlic supplements at least one to two weeks before a planned procedure.

People with stomach or digestive problems may find garlic irritating. If you are taking blood thinners or other medicines, check with your pharmacist before starting a garlic supplement.

Pregnancy and breastfeeding: Eating garlic in normal food amounts is likely fine. There is not enough reliable information about the safety of concentrated garlic supplements during pregnancy or breastfeeding, so it is best to avoid supplement-level doses unless your doctor approves.

Side effects

The most common side effects of garlic are bad breath and body odor. Other possible effects include heartburn, an upset stomach, gas, and nausea, which are more likely with raw garlic or high doses.

Some people develop skin irritation or a rash when handling raw garlic, and allergic reactions are possible. Rarely, garlic may increase the risk of bleeding or bruising. Applying raw garlic directly to the skin can cause burns.

Garlic: Reported Adverse Effects

Documented safety reports on Garlic from the evidence-graded Natural Medicines (TRC Healthcare) database, shown word-for-word from the licensed record.

Orally, garlic is generally well tolerated. Topically, garlic seems to be well tolerated. Intravenously, there is insufficient reliable information available about adverse effects.

Most Common Adverse Effects:

Orally: Abdominal pain, body odor, flatulence, malodorous breath, and nausea. Allergic reactions in sensitive individuals.

Topically: Burns and dermatitis with fresh garlic.

Serious Adverse Effects (Rare):

Orally: Some case reports raise concerns about increased risk of bleeding with garlic.

Reports by condition
Acne Dermatologic

Orally, garlic may cause pruritus, flushing, and acne. Oral intake of a specific garlic product containing allicin (Allimax) has been associated with a case of pruritic rash. Enteric-coated garlic tablets standardized to 1.5% allicin have also been associated with a case of pruritus. Garlic has also been associated with a case of superficial pemphigus in a 49-year-old male with type 2 diabetes. Garlic-induced oral ulcers have also been reported.

Topically, garlic may cause contact dermatitis and urticaria, as well as contact cheilitis. Fresh garlic may be more likely to elicit a reaction than garlic extract. Most reactions have resolved following withdrawal of garlic therapy. In one case report, applying crushed garlic on the neck to help ease a sore throat resulted in an itchy, burning, erythematous lesion in a young female patient. The lesion healed after one week of treatment with topical antibiotics, steroids, and antihistamine ointments. Cases of occupational eczema or dermatitis have been reported in cooks, food handlers, and caterers. According to one case report, dermatitis appeared in chefs exposed to garlic. Treatment with acitretin 25 mg daily or topical psoralen-ultraviolet A (PUVA) for 12 weeks proved effective in mitigating the symptoms. A 34-year-old female with a history of hand dermatitis and paronychia had a worsening of these conditions after peeling raw garlic. She had a positive skin patch test to fresh, raw garlic but not to any other tested allergens, and the conditions resolved when she avoided contact with garlic. Topically, garlic may also cause chemical burns, usually within 12 hours of application. Second- and third-degree chemical burns have been reported in adults, children, and infants exposed to topical garlic, often as an unintended consequence of using garlic medicinally on the skin. A case of painful blisters on the soles of the feet of a 23-year-old Chinese female has been attributed to chemical burns caused by applying crushed raw garlic for 3 hours. Topically, garlic may also cause hyperpigmentation, ulcers, necrotic lesions, facial flushing, and local irritation. In one case report, applying crushed raw garlic to the palatal mucosa for several minutes to relieve mouth pain resulted in a chemical burn that produced a 3 cm necrotic ulcer in an adult female with trigeminal neuralgia.

  1. Tanamai, J., Veeramanomai, S., and Indrakosas, N. The efficacy of cholesterol-lowering action and side effects of garlic enteric coated tablets in man. J Med Assoc.Thai. 2004;87(10):1156-1161.
  2. Lissiman, E., Bhasale, A. L., and Cohen, M. Garlic for the common cold. Cochrane.Database.Syst.Rev. 2012;3:CD006206.
  3. Jafari F, Tabarrai M, Abbassian A, Jafari F, Ayati MH. Effect of Garlic (Allium sativum) Supplementation on Premenstrual Disorders: A Randomized, Double-Blind, Placebo-Controlled Trial. Evid Based Complement Alternat Med 2021;2021:9965064.
  4. Ruocco, V., Brenner, S., and Lombardi, M. L. A case of diet-related pemphigus. Dermatology 1996;192(4):373-374.
  5. Kianoush, S., Balali-Mood, M., Mousavi, S. R., Moradi, V., Sadeghi, M., Dadpour, B., Rajabi, O., and Shakeri, M. T. Comparison of therapeutic effects of garlic and d-Penicillamine in patients with chronic occupational lead poisoning. Basic Clin.Pharmacol
  6. Lee TY, Lam TH. Contact dermatitis due to topical treatment with garlic in Hong Kong. Contact Dermatitis 1991;24:193-6.
  7. Bruynzeel DP. Bulb dermatitis. Dermatological problems in the flower bulb industries. Contact Dermatitis 1997;37:70-7.
  8. Kanerva L, Estlander T, Jolanki R. Occupational allergic contact dermatitis from spices. Contact Dermatitis 1996;35:157-62.
  9. Pereira, F., Hatia, M., and Cardoso, J. Systemic contact dermatitis from diallyl disulfide. Contact Dermatitis 2002;46(2):124.
  10. Hughes, T. M., Varma, S., and Stone, N. M. Occupational contact dermatitis from a garlic and herb mixture. Contact Dermatitis 2002;47(1):48.
  11. Laing, M. E., Barry, J., Buckley, A. M., and Murphy, G. M. Immediate and delayed hypersensitivity reactions to food and latex in a chef. Contact Dermatitis 2006;55(3):193-194.
  12. McFadden, J. P., White, J. M., Basketter, D. A., and Kimber, I. Reduced allergy rates in atopic eczema to contact allergens used in both skin products and foods: atopy and the 'hapten-atopy hypothesis'. Contact Dermatitis 2008;58(3):156-158.
  13. Bordel-Gomez, M. T. and Miranda-Romero, A. Sensitivity to diallyl disulfide in a Spanish population. Contact Dermatitis 2008;59(2):125-126.
  14. Takeuchi, S., Matsuzaki, Y., Ikenaga, S., Nishikawa, Y., Kimura, K., Nakano, H., and Sawamura, D. Garlic-induced irritant contact dermatitis mimicking nail psoriasis. J.Dermatol. 2011;38(3):280-282.
  15. Kaplan, B., Schewach-Millet, M., and Yorav, S. Factitial dermatitis induced by application of garlic. Int J Dermatol. 1990;29(1):75-76.
  16. Yoshikawa, K., Hadame, K., Saitoh, K., and Hijikata, T. Patch tests with common vegetables in hand dermatitis patients. Contact Dermatitis 1979;5(4):274-275.
  17. Bleumink, E., Doeglas, H. M., Klokke, A. H., and Nater, J. P. Allergic contact dermatitis to garlic. Br.J Dermatol. 1972;87(1):6-9.
  18. Mitchell, J. C. Contact sensitivity to garlic (Allium). Contact Dermatitis 1980;6(5):356-357.
  19. Edelstein AJ and Johnstown PA. Dermatitis caused by garlic. Arch Dermatol 1950;61:111.
  20. Fleischer S, Bayerl C, and Jung EG. [Occupational allergic hand dermatitis to garlic in a pizza baker]. Aktuelle Dermatol 1996;22:278-279.
  21. Gaddoni G, Selvi M, Resta F, and et al. Allergic contact dermatitis to garlic in a cook. Ann Ital Dermatol Clin Sperimentale 1994;48:120-121.
  22. Jamaluddin J, Jamil SN. An unexpected reaction to topical garlic medicament - A case report of irritant contact dermatitis successfully managed in primary care. Cureus 2023;15(1):e33657.
  23. Ekeowa-Anderson, A. L., Shergill, B., and Goldsmith, P. Allergic contact cheilitis to garlic. Contact Dermatitis 2007;56(3):174-175.
  24. Karabacak E, Aydin E, Kutlu A, Dogan B. An unusual garlic burn occurring on an unexpected area. BMJ Case Rep 2014.
  25. van Ketel, W. G. and de Haan, P. Occupational eczema from garlic and onion. Contact Dermatitis 1978;4(1):53-54.
  26. Eming, S. A., Piontek, J. O., Hunzelmann, N., Rasokat, H., and Scharffetter-Kachanek, K. Severe toxic contact dermatitis caused by garlic. Br J Dermatol. 1999;141(2):391-392.
  27. Hjorth, N. and Roed-Petersen, J. Occupational protein contact dermatitis in food handlers. Contact Dermatitis 1976;2(1):28-42.
  28. McFadden, J. P., White, I. R., and Rycroft, R. J. Allergic contact dermatitis from garlic. Contact Dermatitis 1992;27(5):333-334.
  29. Hubbard VG, Goldsmith P. Garlic-fingered chefs. Contact Dermatitis 2005;52:165-6.
  30. Dev T, Bharti P, Patel U, Bhari N. Chronic paronychia and nail dystrophy: an atypical presentation of allergic contact dermatitis to garlic. Int J Dermatol 2021 Feb 11. doi: 10.1111/ijd.15430.
  31. Garty BZ. Garlic burns. Pediatrics 1993;91:658-9.
  32. Cronin E. Dermatitis of the hands in caterers. Contact Dermatitis 1987;17:265-9.
  33. Rafaat, M. and Leung, A. K. Garlic burns. Pediatr Dermatol. 2000;17(6):475-476.
  34. Hviid, K. and Alsbjorn, B. ["Burns" caused by local application of garlic]. Ugeskr.Laeger 12-11-2000;162(50):6853-6854.
  35. Baruchin, A. M., Sagi, A., Yoffe, B., and Ronen, M. Garlic burns. Burns 2001;27(7):781-782.
  36. Lachter, J., Babich, J. P., Brookman, J. C., and Factor, A. Y. Garlic: a way out of work. Mil.Med 2003;168(6):499-500.
  37. Friedman, T., Shalom, A., and Westreich, M. Self-inflicted garlic burns: our experience and literature review. Int.J Dermatol. 2006;45(10):1161-1163.
  38. Bagga, S., Thomas, B. S., and Bhat, M. Garlic burn as self-inflicted mucosal injury--a case report and review of the literature. Quintessence.Int. 2008;39(6):491-494.
  39. Filobbos, G., Chapman, T., and Gesakis, K. Iatrogenic burns from garlic. J.Burn Care Res. 2012;33(1):e21.
  40. Parish, R. A., McIntire, S., and Heimbach, D. M. Garlic burns: a naturopathic remedy gone awry. Pediatr.Emerg.Care 1987;3(4):258-260.
  41. Canduela, V., Mongil, I., Carrascosa, M., Docio, S., and Cagigas, P. Garlic: always good for the health? Br J Dermatol. 1995;132(1):161-162.
  42. Farrell, A. M. and Staughton, R. C. Garlic burns mimicking herpes zoster. Lancet 4-27-1996;347(9009):1195.
  43. Rance, F. and Dutau, G. Labial food challenge in children with food allergy. Pediatr Allergy Immunol. 1997;8(1):41-44.
  44. Roberge, R. J., Leckey, R., Spence, R., and Krenzelok, E. J. Garlic burns of the breast. Am J Emerg.Med 1997;15(5):548.
  45. Xu S, Heller M, Wu PA, Nambudri VE. Chemical burn caused by topical application of garlic under occlusion. Dermatol Online J 2014;20(1):21261.
  46. Oberle M, Wachs T, Brisson P. Garlic burn to the face. J Spec Oper Med. Winter 2016;16(4):80-81.
  47. Russell, J. E. Chinese complementary therapy for stress causing bilateral chemical burns to the feet. Emerg.Med.J. 2010;27(10):787.
  48. Dehghani F, Merat A, Panjehshahin MR, Handjani F. Healing effect of garlic extract on warts and corns. Int J Dermatol 2005;44:612-5.
  49. Dillon, S. A., Burmi, R. S., Lowe, G. M., Billington, D., and Rahman, K. Antioxidant properties of aged garlic extract: an in vitro study incorporating human low density lipoprotein. Life Sci. 2-21-2003;72(14):1583-1594.
  50. Groppo, F. C., Ramacciato, J. C., Simoes, R. P., Florio, F. M., and Sartoratto, A. Antimicrobial activity of garlic, tea tree oil, and chlorhexidine against oral microorganisms. Int.Dent.J. 2002;52(6):433-437.
  51. Tomo S, Santos IDS, Cruz TMD, Miyahara GI, Simonato LE. Garlic burn trauma of the oral mucosa in a patient with trigeminal neuralgia: A case report. Dent Traumatol 2022.
Allergic rhinitis (hay fever) Immunologic

There is a case report of an immediate sensitivity reaction to oral raw garlic, resulting in wheals, in a 31-year-old female. The patient did not react to cooked garlic, and skin prick tests showed allergy only to raw garlic. Researchers note that at least some allergens in raw garlic are heat labile. This suggests that consuming cooked rather than raw garlic may help avoid this reaction in patients allergic to raw garlic. However, different people react to different allergens in garlic. At least some of these allergens are heat stable. While rare, garlic-induced anaphylaxis has been reported.

Topically, allergic contact dermatitis has been reported in case reports.

  1. Yagami A, Suzuki K, Sano A, et al. Immediate allergy due to raw garlic (Allium sativum L.). J Dermatol. 2015;42(10):1026-7.
  2. Ma S, Yin J. Anaphylaxis induced by ingestion of raw garlic. Foodborne Pathog Dis 2012;9(8):773-5.
  3. Treudler R, Reuter A, Engin AM, Simon JC. A case of anaphylaxis after garlic ingestion: Is alliinase the only culprit allergen? J Investig Allergol Clin Immunol. 2015;25(5):374-5.
  4. Lembo, G., Balato, N., Patruno, C., Auricchio, L., and Ayala, F. Allergic contact dermatitis due to garlic (Allium sativum). Contact Dermatitis 1991;25(5):330-331.
  5. Bojs, G. and Svensson, A. Contact allergy to garlic used for wound healing. Contact Dermatitis 1988;18(3):179-181.
  6. Bleumink, E. and Nater, J. P. Contact dermatitis to garlic; crossreactivity between garlic, onion and tulip. Arch.Dermatol.Forsch 8-15-1973;247(2):117-124.
  7. Papageorgiou, C., Corbet, J. P., Menezes-Brandao, F., Pecegueiro, M., and Benezra, C. Allergic contact dermatitis to garlic (Allium sativum L.). Identification of the allergens: the role of mono-, di-, and trisulfides present in garlic. A comparative stu
  8. Delaney, T. A. and Donnelly, A. M. Garlic dermatitis. Austr J Dermatol 1996;37(2):109-110.
Anorexia Gastrointestinal

Orally, dehydrated garlic preparations or raw garlic may cause malodorous breath, body odor, abdominal pain or fullness, anorexia, diarrhea, constipation, flatulence, belching, heartburn, nausea, unpleasant taste, reflux, and bowel obstruction.

Large quantities of garlic may damage the gastrointestinal tract. In one case report, a patient taking garlic for hypertension reported odynophagia and retrosternal pain after taking garlic without any water the previous day. An esophageal lesion 3 cm in length was detected upon endoscopy. The symptoms resolved 3 days after starting a liquid diet and taking lansoprazole 30 mg twice daily and sucralfate four times daily. One case of bowel obstruction was reported in a 66-year-old male who ingested an entire garlic bulb. Esophageal perforation has been reported in at least 17 individuals who consumed entire garlic cloves. In one case the perforation led to mediastinitis and death.

Garlic has also been associated with eosinophilic infiltration of the gastrointestinal tract. In one case report a 42-year-old female presented with symptoms of eosinophilic gastroenteritis, which included pollinosis, asthma, diarrhea, heart burn, peripheral eosinophilia, and urticaria. After stopping use of garlic and sesame, the patient improved. In a case report of eosinophilic esophagitis, garlic was determined to be the causative agent in a patient with long-standing gastrointestinal symptoms. The patient had attempted to treat upper gastrointestinal symptoms as gastrointestinal reflux disease without success for many years. Skin prick testing showed a positive reaction to garlic, of which the patient noted frequent consumption. Marked symptom improvement was noted within 3 weeks of garlic avoidance.

Intravenously, garlic 1 mg/kg of body weight daily diluted into 500 mL saline and administered over 4 hours has been reported to cause abdominal discomfort, vomiting, diarrhea, nausea, anorexia, flatulence, weight loss, and garlicky body odor.

Clinical research suggests that patients with metabolic syndrome taking 1600 mg of powdered garlic by mouth daily for 3 months may experience improved intestinal transit time when compared with placebo, suggesting that garlic powder may reduce symptoms of constipation.

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  2. Hansanugrum, A. and Barringer, S. A. Effect of milk on the deodorization of malodorous breath after garlic ingestion. J.Food Sci. 8-1-2010;75(6):C549-C558.
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  6. Simons LA, Balasubramaniam S, von Konigsmark M, et al. On the effect of garlic on plasma lipids and lipoproteins in mild hypercholesterolaemia. Atherosclerosis 1995;113:219-25.
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  8. Koscielny J, Klussendorf D, Latza R, et al. The antiatherosclerotic effect of Allium sativum. Atherosclerosis 1999;144:237-49.
  9. Ziaei S, Hantoshzadeh S, Rezasoltani P, Lamyian M. The effect of garlic tablet on plasma lipids and platelet aggregation in nulliparous pregnants at high risk of preeclampsia. Eur J Obstet Gynecol Reprod Biol 2001;99:201-6..
  10. Josling P. Preventing the common cold with a garlic supplement: a double-blind, placebo-controlled survey. Adv Ther 2001;18:189-93.
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  13. Groppo, F. C., Ramacciato, J. C., Simoes, R. P., Florio, F. M., and Sartoratto, A. Antimicrobial activity of garlic, tea tree oil, and chlorhexidine against oral microorganisms. Int.Dent.J. 2002;52(6):433-437.
  14. Tanamai, J., Veeramanomai, S., and Indrakosas, N. The efficacy of cholesterol-lowering action and side effects of garlic enteric coated tablets in man. J Med Assoc.Thai. 2004;87(10):1156-1161.
  15. Kianoush, S., Balali-Mood, M., Mousavi, S. R., Moradi, V., Sadeghi, M., Dadpour, B., Rajabi, O., and Shakeri, M. T. Comparison of therapeutic effects of garlic and d-Penicillamine in patients with chronic occupational lead poisoning. Basic Clin.Pharmacol
  16. Yeh YY, Lin RI, Yeh SM, and et al. Garlic reduces plasma cholesterol in hypercholesterolemic men maintaining habitual diets. In: Ohigashi H, Osawa T, Terao J, and et al. Food Factors for Cancer Prevention. Tokyo, Japan: Springer-Verlag;1997.
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  25. Bakhshi, M., Taheri, J. B., Shabestari, S. B., Tanik, A., and Pahlevan, R. Comparison of therapeutic effect of aqueous extract of garlic and nystatin mouthwash in denture stomatitis. Gerodontology. 2012;29(2):e680-e684.
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  34. Bhat GS, Shastry A. Prospective, randomized, placebo-controlled, two-arm study to evaluate the efficacy of coadministration of garlic as a hydrogen sulfide donor and tadalafil in patients with erectile dysfunction not responding to tadalafil alone - A pil
  35. Ergul B, Cakal B. Dysphagia caused by garlic induced esophagitis. Clin Res Hepatol Gastroenterol 2012;36(6):e134.
  36. Szybejko, J., Zukowski, A., and Herbec, R. [Unusual cause of obturation of the small intestine]. Wiad.Lek. 4-15-1982;35(2):163-164.
  37. Gandomkar H, Mahmoodzadeh H, Tavakoli H, Fazeli M, Rezaei J. Garlic-induced esophageal perforation: A case series. Asian J Surg. 2020;43(6):696-697.
  38. Adachi, A. [Two cases of eosinophilic gastroenteritis whose causative allergens are usefully diagnosed by patch test]. Arerugi 2010;59(5):545-551.
  39. Mane SK, Jordan PA, Bahna SL. Eosinophilic esophagitis to unsuspected rare food allergen. Ann Allergy Asthma Immunol 2013;111(1):64-5.
  40. Davis, L. E., Shen, J. K., and Cai, Y. Antifungal activity in human cerebrospinal fluid and plasma after intravenous administration of Allium sativum. Antimicrob.Agents Chemother. 1990;34(4):651-653.
  41. Sangouni AA, Alizadeh M, Jamalzehi A, Hosseinzadeh M, Parastouei K. Garlic supplementation improves intestinal transit time, lipid accumulation product and cardiometabolic indices in subjects with metabolic syndrome: A randomized controlled trial. Phytoth
Asthma Pulmonary/Respiratory

Garlic exposure, most notably in occupational settings, may cause asthma and other symptoms such as sneezing, nasal obstruction, rhinorrhea, and sinusitis. A case of minor hemoptysis has been reported for one patient with cystic fibrosis following intake of garlic capsules orally once daily for 8 weeks. A 77-year-old female developed pneumonia related to the intake of one whole black garlic clove daily. The cloves were prepared by heating a whole garlic bulb in a pot for one month. Symptoms included dyspnea and coughing, and test results were positive for lymphocyte-induced stimulation by black garlic and raw garlic. The patient required treatment with oral steroids and was told to avoid garlic.

  1. van der Walt, A., Lopata, A. L., Nieuwenhuizen, N. E., and Jeebhay, M. F. Work-related allergy and asthma in spice mill workers - The impact of processing dried spices on IgE reactivity patterns. Int Arch.Allergy Immunol. 2010;152(3):271-278.
  2. Seuri, M., Taivanen, A., Ruoppi, P., and Tukiainen, H. Three cases of occupational asthma and rhinitis caused by garlic. Clin Exp.Allergy 1993;23(12):1011-1014.
  3. Smyth, A. R., Cifelli, P. M., Ortori, C. A., Righetti, K., Lewis, S., Erskine, P., Holland, E. D., Givskov, M., Williams, P., Camara, M., Barrett, D. A., and Knox, A. Garlic as an inhibitor of Pseudomonas aeruginosa quorum sensing in cystic fibrosis--a p
  4. Suzuki Y, Saito J, Misa K, Fukuhara N, Fukuhara A, Munakata M. A case of black garlic-induced pneumonia as an adverse reaction. Allergol Int. 2016;65(3):353-5.
Back pain Musculoskeletal

Orally, garlic has been associated with individual cases of gout and low back pain, but it is not clear if these adverse events can be attributed to garlic.

  1. Lissiman, E., Bhasale, A. L., and Cohen, M. Garlic for the common cold. Cochrane.Database.Syst.Rev. 2012;3:CD006206.
  2. Kianoush, S., Balali-Mood, M., Mousavi, S. R., Moradi, V., Sadeghi, M., Dadpour, B., Rajabi, O., and Shakeri, M. T. Comparison of therapeutic effects of garlic and d-Penicillamine in patients with chronic occupational lead poisoning. Basic Clin.Pharmacol
Insomnia Neurologic/CNS

Orally, dizziness, insomnia, headaches, diaphoresis, fever, chills, somnolence, increased appetite, euphoria, and weight loss have been reported with garlic. In one case, the smell of garlic was identified as a trigger for migraines in a 32-year-old female. The subject reported fortification spectra along with visual spots for a few seconds followed by instantaneous biparietal, crushing level (10/10) headaches upon exposure to the scent of garlic or onion.

  1. Macan H, Uykimpang R, Alconcel M, et al. Aged garlic extract may be safe for patients on warfarin therapy. J Nutr 2006;136(3 Suppl):793S-795S.
  2. Huang, J., Frohlich, J., and Ignaszewski, A. P. The impact of dietary changes and dietary supplements on lipid profile. Can J Cardiol 2011;27(4):488-505.
  3. Tanamai, J., Veeramanomai, S., and Indrakosas, N. The efficacy of cholesterol-lowering action and side effects of garlic enteric coated tablets in man. J Med Assoc.Thai. 2004;87(10):1156-1161.
  4. Kianoush, S., Balali-Mood, M., Mousavi, S. R., Moradi, V., Sadeghi, M., Dadpour, B., Rajabi, O., and Shakeri, M. T. Comparison of therapeutic effects of garlic and d-Penicillamine in patients with chronic occupational lead poisoning. Basic Clin.Pharmacol
  5. Nantz, M. P., Rowe, C. A., Muller, C. E., Creasy, R. A., Stanilka, J. M., and Percival, S. S. Supplementation with aged garlic extract improves both NK and gammadelta-T cell function and reduces the severity of cold and flu symptoms: a randomized, double
  6. anonymous. Garlic in cryptococcal meningitis: a preliminary report of 21 cases. Chin Med J (Engl.) 1980;93(2):123-126.
  7. Roussos AP, Hirsch AR. Alliaceous migraines. Headache 2014;54(2):378-82.
Kidney stones (nephrolithiasis) Hematologic

Oral use of dietary garlic or supplements containing garlic has caused platelet dysfunction, increased fibrinolytic activity, prolonged bleeding time, retrobulbar hemorrhage (bleeding behind the eye) postoperative bleeding, and spinal epidural hematoma. Also, a case of kidney hematoma following extracorporeal shock-wave lithotripsy (SWL) has been reported in a patient with nephrolithiasis who took aged garlic. A case of increased bleeding time that complicated epistaxis management has been reported in a patient taking garlic, aspirin, and milk thistle.

Intravenously, garlic has been associated with the development of thrombophlebitis at the injection site.

  1. Rose KD, Croissant PD, Parliament CF, Levin MB. Spontaneous spinal epidural hematoma with associated platelet dysfunction from excessive garlic ingestion: a case report. Neurosurg 1990;26:880-2.
  2. Burnham BE. Garlic as a possible risk for postoperative bleeding. Plast Reconstr Surg 1995;95:213.
  3. Kiesewetter H, Jung F, Jung EM, et al. Effects of garlic coated tablets in peripheral arterial occlusive disease. Clin Investig 1993;71:383-6.
  4. Kiesewetter H, Jung F, Jung EM, et al. Effect of garlic on platelet aggregation in patients with increased risk of juvenile ischaemic attack. Eur J Clin Pharmacol 1993;45:333-6.
  5. Carden SM, Good WV, Carden PA, Good RM. Garlic and the strabismus surgeon. Clin Experiment Ophthalmol 2002;30:303-4.
  6. Gadkari JV, Joshi VD. Effect of ingestion of raw garlic on serum cholesterol level, clotting time and fibrinolytic activity in normal subjects. J Postgrad.Med 1991;37:128-131.
  7. Fedder, S. L. Spinal epidural hematoma and garlic ingestion. Neurosurgery 1990;27(4):659.
  8. Harenberg, J., Giese, C., and Zimmermann, R. Effect of dried garlic on blood coagulation, fibrinolysis, platelet aggregation and serum cholesterol levels in patients with hyperlipoproteinemia. Atherosclerosis 1988;74(3):247-249.
  9. German, K., Kumar, U., and Blackford, H. N. Garlic and the risk of TURP bleeding. Br J Urol 1995;76(4):518.
  10. Petry, J. J. Garlic and postoperative bleeding. Plast.Reconstr.Surg 1995;96(2):483-484.
  11. Jain, R. C. Effect of garlic on serum lipids, coagulability and fibrinolytic activity of blood. Am J Clin Nutr 1977;30(9):1380-1381.
  12. Kumar, M. and Berwal, J. S. Sensitivity of food pathogens to garlic (Allium sativum). J Appl.Microbiol. 1998;84(2):213-215.
  13. Bimmermann A, Weingart K, and Schwartzkopff W. Allium sativum: Studie zur Wirksamkeit bei Hyperlipoproteinamie. Therapiewoche 1988;38:3885-3890.
  14. Czerny B and Samochowiec J. Klinische Untersuchungen mit einem Knoblauch-Lezithin-Präparat. Arztezeitschr Naturheilverf 1996;37:126-129.
  15. Nair A, Abdelqader B, Sureshkumar S, Katmawai-Sabbagh S. Hematuria and dietary supplements - A case report on pronounced bleeding following a minimally invasive urological intervention in a patient on long term garlic supplements. Urol Case Rep 2023;50:10
  16. Gravas S, Tzortzis V Rountas C Melekos MD. Extracorporeal shock-wave lithotripsy and garlic consumption: a lesson to learn. Urol Res. 2010;38(1):61-63.
  17. Shakeel, M., Trinidade, A., McCluney, N., and Clive, B. Complementary and alternative medicine in epistaxis: a point worth considering during the patient's history. Eur.J.Emerg.Med. 2010;17(1):17-19.
  18. Davis, L. E., Shen, J. K., and Cai, Y. Antifungal activity in human cerebrospinal fluid and plasma after intravenous administration of Allium sativum. Antimicrob.Agents Chemother. 1990;34(4):651-653.
Myasthenia gravis Genitourinary

Orally, garlic might cause dysuria, hematuria, or polyuria. In one case, an older male with high dietary and supplemental garlic intake at doses of 300-5400 mg daily for 3-4 years developed severe hematuria with clots after undergoing a minimally invasive prostate procedure.

  1. Smyth, A. R., Cifelli, P. M., Ortori, C. A., Righetti, K., Lewis, S., Erskine, P., Holland, E. D., Givskov, M., Williams, P., Camara, M., Barrett, D. A., and Knox, A. Garlic as an inhibitor of Pseudomonas aeruginosa quorum sensing in cystic fibrosis--a p
  2. Hurley, M. N., Forrester, D. L., and Smyth, A. R. Antibiotic adjuvant therapy for pulmonary infection in cystic fibrosis. Cochrane.Database.Syst.Rev. 2010;(10):CD008037.
  3. Kianoush, S., Balali-Mood, M., Mousavi, S. R., Moradi, V., Sadeghi, M., Dadpour, B., Rajabi, O., and Shakeri, M. T. Comparison of therapeutic effects of garlic and d-Penicillamine in patients with chronic occupational lead poisoning. Basic Clin.Pharmacol
  4. Nair A, Abdelqader B, Sureshkumar S, Katmawai-Sabbagh S. Hematuria and dietary supplements - A case report on pronounced bleeding following a minimally invasive urological intervention in a patient on long term garlic supplements. Urol Case Rep 2023;50:10
DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.

Adverse-effects data: Natural Medicines, Therapeutic Research Center

Dosing

There is no single official dose for garlic supplements. Products vary widely in their strength and in how much allicin or other active compounds they provide, which makes comparing doses difficult.

Because of this, it is best to follow the directions on the product label and ask your pharmacist for help choosing a product. Different forms, such as aged garlic extract, powdered tablets, and oil, are not interchangeable. Start low and watch how you respond.

Pregnancy & Breastfeeding

Garlic & Pregnancy

Likely Safe

When used orally in amounts commonly found in foods.

  1. Bloch AS. Pushing the Envelope of Nutrition Support: Complementary Therapies. Nutrition 2000;16:236-9.
Possibly Unsafe

When used orally in medicinal amounts. Garlic is reported to have abortifacient activity. One study also suggests that garlic constituents are distributed to the amniotic fluid after a single dose of garlic. However, there are no published reports of garlic adversely affecting pregnancy. In clinical research, garlic 800 mg daily was used during the third trimester of pregnancy with no reported adverse outcomes. There is insufficient reliable information available about the safety of topical garlic during pregnancy.

  1. Farnsworth N, Bingel A, Cordell G, et al. Potential value of plants as sources of new antifertility agents I. J Pharm Sci 1975;64:535-98.
  2. Mennella JA, Johnson A, Beauchamp GK. Garlic ingestion by pregnant women alters the odor of amniotic fluid. Chem Senses 1995;20:207-9.
  3. Ziaei S, Hantoshzadeh S, Rezasoltani P, Lamyian M. The effect of garlic tablet on plasma lipids and platelet aggregation in nulliparous pregnants at high risk of preeclampsia. Eur J Obstet Gynecol Reprod Biol 2001;99:201-6..
  4. Soltani PR. Preecampisia [sic] is an important complication of pregnancy which can result in morbidity and mortality in mother, fetus and the neonate. Journal of Medical Council of Islamic Republic of Iran (J MED COUNC ISLAMIC REPUB IRAN) 2005;23(3):319.

Garlic & Breastfeeding

Likely Safe

When used orally in amounts commonly found in foods.

  1. Bloch AS. Pushing the Envelope of Nutrition Support: Complementary Therapies. Nutrition 2000;16:236-9.
Possibly Unsafe

When used orally in amounts greater than those found in foods. Several small studies suggest that garlic constituents are secreted in breast milk, and that nursing infants of mothers consuming garlic are prone to extended nursing. There is insufficient reliable information available about the safety of topical garlic during lactation.

  1. Bloch AS. Pushing the Envelope of Nutrition Support: Complementary Therapies. Nutrition 2000;16:236-9.
  2. Mennella JA, Beauchamp GK. Maternal diet alters the sensory qualities of human milk and the nursling's behavior. Pediatrics 1991;88:737-44.
  3. Mennella JA, Beauchamp GK. The effects of repeated exposure to garlic-flavored milk on the nursling's behavior. Pediatr Res 1993;34:805-8.
DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.

© 2026 Therapeutic Research Center

Pregnancy & lactation ratings: Natural Medicines, Therapeutic Research Center

References & further reading

The 154 references that drive our Garlic monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. Silagy CA, Neil HA. A meta-analysis of the effect of garlic on blood pressure. J Hypertens 1994;12:463-8. DOI
  2. McMahon FG, Vargas R. Can garlic lower blood pressure? A pilot study. Pharmacotherapy 1993;13:406-7. DOI
  3. Auer W, Eiber A, Hertkorn E, et al. Hypertension and hyperlipidaemia: garlic helps in mild cases. Br J Clin Pract Suppl 1990;69:3-6.
  4. Garty BZ. Garlic burns. Pediatrics 1993;91:658-9.
  5. Rose KD, Croissant PD, Parliament CF, Levin MB. Spontaneous spinal epidural hematoma with associated platelet dysfunction from excessive garlic ingestion: a case report. Neurosurg 1990;26:880-2. PubMed
  6. Burnham BE. Garlic as a possible risk for postoperative bleeding. Plast Reconstr Surg 1995;95:213.
  7. Sunter WH. Warfarin and garlic. Pharm J 1991;246:722.
  8. Berthold HK, Sudhop T, von Bergmann K. Effect of a garlic oil preparation on serum lipoproteins and cholesterol metabolism. JAMA 1998;279:1900-2.
  9. Steiner M, Khan AH, Holbert D, Lin RI. A double-blind crossover study in moderately hypercholesterolemic men that compared the effect of aged garlic extract and placebo administration on blood lipids. Am J Clin Nutr 1996;64:866-70. PubMed
  10. Steiner M, Lin RS. Changes in platelet function and susceptibility of lipoproteins to oxidation associated with administration of aged garlic extract. J Cardiovasc Pharmacol 1998;31:904-8. PubMed
  11. Gwilt PR, Lear CL, Tempero MA, et al. The effect of garlic extract on human metabolism of acetaminophen. Cancer Epidemiol Biomarkers Prev 1994;3:155-60.
  12. Rahman K, Billington D. Dietary supplementation with aged garlic extract inhibits ADP-induced platelet aggregation in humans. J Nutr 2000;130:2662-5. PubMed
  13. Bloch AS. Pushing the Envelope of Nutrition Support: Complementary Therapies. Nutrition 2000;16:236-9. PubMed
  14. Steiner M, Li W. Aged garlic extract, a modulator of cardiovascular risk factors: a dose-finding study on the effects of AGE on platelet functions. J Nutr 2001;131:980S-4S. PubMed
  15. Mader FH. Treatment of hyperlipidaemia with garlic-powder tablets. Evidence from the German Association of General Practitioners' multicentric placebo-controlled double-blind study. Arzneimittelforschung 1990;40:1111-6.
Keep reading

This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

Brand directory

Brands that make products with Garlic

727 brands in our database make a supplement containing Garlic.

Product directory

Supplement products with Garlic

4,212 products in our database contain Garlic. Open any to see its full ingredient list and every drug interaction we check.

#3 - GB-LIV by Nutri-West Herbals Tablet Or Pill 100 Tablet(s) View ingredients & interactions #4 - B -P by Nutri-West Herbals Tablet Or Pill 100 Tablet(s) View ingredients & interactions +G Boost Garlic Complex by Shaklee Tablet Or Pill 240 Tablet(s) View ingredients & interactions 1 Detoxify With Deep Liver And Organ Cleanse by Renew Life Capsule 14 Capsule(s) View ingredients & interactions 1 Week Flush by MH Michael's Health Naturopathic Programs Tablet Or Pill 84 Vegetarian Tablet(s) View ingredients & interactions 20 Veggies & Mushrooms by PureMax Labs YummyVite Capsule 60 Capsule(s) View ingredients & interactions 3 Bactrex by Systemic Formulas Inc Capsule 60 Capsule(s) View ingredients & interactions 50 & Wiser Men by Garden of Life Vitamin Code Capsule 240 Vegetarian Capsule(s) View ingredients & interactions 50 & Wiser Men by Garden of Life Vitamin Code Capsule 240 Vegetarian Capsule(s) View ingredients & interactions 50 & Wiser Men by Garden of Life Vitamin Code Capsule 120 Vegetarian Capsule(s) View ingredients & interactions 50 & Wiser Men by Garden of Life Vitamin Code Capsule 240 Vegetarian Capsule(s) View ingredients & interactions 50 & Wiser Men by Garden of Life Vitamin Code Capsule 120 Vegetarian Capsule(s) View ingredients & interactions 50 & Wiser Men by Garden of Life Vitamin Code Capsule 120 Vegetarian Capsule(s) View ingredients & interactions 50 & Wiser Women by Garden of Life Vitamin Code Capsule 120 Vegetarian Capsule(s) View ingredients & interactions 50 & Wiser Women by Garden of Life Vitamin Code Capsule 120 Vegetarian Capsule(s) View ingredients & interactions 50 & Wiser Women by Garden of Life Vitamin Code Capsule 240 Vegetarian Capsule(s) View ingredients & interactions 50 & Wiser Women by Garden of Life Vitamin Code Capsule 240 Vegetarian Capsule(s) View ingredients & interactions 50 & Wiser Women by Garden of Life Vitamin Code Capsule 120 Vegetarian Capsule(s) View ingredients & interactions 50 & Wiser Women by Garden of Life Vitamin Code Capsule 240 Vegetarian Capsule(s) View ingredients & interactions 50 & Wiser Women by Garden of Life Vitamin Code Capsule 120 Vegetarian Capsule(s) View ingredients & interactions 7 in 1 Organic Immune Support by Number One Nutrition Tablet Or Pill 90 Tablet(s) View ingredients & interactions 7-Day Cleanse by Vitabase Capsule 21 Packet(s) View ingredients & interactions A-Biotic by Protocol For Life Balance Softgel Capsule 60 Softgel(s) View ingredients & interactions A-Biotic by Protocol For Life Balance Softgel Capsule 60 Softgel(s) View ingredients & interactions
Pharmacist Counseling Corner

Garlic: Common Questions

What is Garlic used for, and does it work?
People use Garlic for many reasons, but the evidence varies by use. According to the Natural Medicines database, there is at least some clinical evidence supporting Garlic for Atherosclerosis, Diabetes, Endometriosis and Hypertension. For most other uses it has been studied for, the evidence is currently insufficient to rate. See the graded list on this page, and always confirm with your pharmacist or doctor.
Does Garlic interact with prescription medications?
Yes. We list 989 medications with a known interaction with Garlic. Use the checker above to see how Garlic interacts with a specific drug.
How are Garlic interactions rated?
Each interaction is graded major, moderate, or minor based on how clinically significant it is and the strength of the evidence behind it. Major interactions are the most serious and are best avoided, or used only under close professional supervision.
Is it safe to take Garlic with my medications?
It depends on the specific medication. Some combinations are fine, while others call for monitoring, timing changes, or should be avoided. Check your exact drug above and confirm with your pharmacist or doctor before starting, stopping, or changing anything.
Where does this Garlic interaction information come from?
Our interaction data is built on the Natural Medicines database — an evidence-graded reference for vitamins, herbs, and supplements — and is reviewed by licensed HelloPharmacist pharmacists, who may add clinical context.
What is Garlic used for?
People most often use Garlic supplements for heart health, high blood pressure, and high cholesterol, and sometimes for immune support. The evidence is strongest for small blood pressure benefits and is weaker for most other uses.
Is Garlic safe to take every day?
Garlic as food is safe for most people daily. Supplements are usually well tolerated but can cause breath and body odor, stomach upset, and a slightly higher bleeding risk, so check with your pharmacist if you plan to take it long term.
Can I take Garlic supplements while pregnant or breastfeeding?
Eating Garlic in normal food amounts is generally considered fine. There isn't enough reliable safety information on concentrated Garlic supplements during pregnancy or breastfeeding, so avoid supplement doses unless your doctor approves.
Does aged Garlic extract work better than regular Garlic?
Aged Garlic extract has less odor and is one of the more studied forms, but no form is clearly proven superior. Different products contain different active compounds, so they are not directly interchangeable.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Products that contain Garlic

A rotating sample of real supplements in our database that list Garlic — open any to see its full ingredients and every drug interaction we check.

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