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Dietary supplement

Onion Ingredients & Drug Interactions

by Herbal Terra

Onion label
See full label image
Liquid Category: Botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Onion against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

Onion is a dietary supplement by Herbal Terra with 1 active ingredient. Its ingredients are commonly taken for colds and respiratory symptoms, heart and cholesterol health, blood sugar support.Based on those ingredients, 275 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are certified organic Onion dried bulb liquid extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Onion by Herbal Terra

Ask about any prescription or over-the-counter medication and we check it for interactions with Onion by Herbal Terra — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Onion by Herbal Terra

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 11, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

Herbal Terra's Onion is a single-ingredient liquid extract made from certified organic onion dried bulb. The liquid is prepared using a menstruum — a solvent used in herbal extraction — to concentrate the onion's active compounds.

Onion contains compounds that research suggests can affect blood clotting, blood sugar levels, and how your body metabolizes certain drugs. This is a concentrated supplement form, quite different from eating onions as a food.

Does it work?

Moderate evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed

This product doesn't appear to be marketed for a specific use, so we graded Onion's overall clinical evidence instead.

Moderate

Some clinical evidence supports Onion for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredient's overall clinical evidence instead.
  • On file: Scarring — rated "Possibly Effective" (Natural Medicines).

The evidence for onion supplements is mixed and often limited. It's rated possibly effective for scarring, but possibly ineffective for obesity.

For other uses — including alopecia areata (patchy hair loss), angina (chest pain), and atherosclerosis (arterial plaque buildup) — we don't have enough reliable evidence to say whether it works or doesn't. If you're considering this supplement for a specific condition, talk with your pharmacist about what the current research actually shows for your situation.

The evidence, ingredient by ingredient Onion

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

As a food, onion is well tolerated by most people. However, this is a concentrated supplement, and concentrated doses aren't as well studied as regular food amounts.

The most common side effects from onion taken by mouth are abdominal pain and heartburn. When applied topically, eczema and irritation can occur.

Allergy to onion is rare, but when it does happen, it can be serious — there are reports of anaphylaxis (a severe allergic reaction), throat closing, and migraine triggered by onion smell or exposure. Consuming large quantities of onion or onion powder can also cause stomach distress or, in rare cases, esophageal spasm.

Because concentrated supplement doses aren't well studied, you should avoid them if you're pregnant or breastfeeding until you've talked with your doctor or pharmacist.

Side effects, ingredient by ingredient Onion

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Onion.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications; lithium.
  • For scale: 275 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before you start this onion extract, double-check if you take any blood thinners or antiplatelet drugs (like warfarin or clopidogrel) — onion may increase bleeding risk. Also screen diabetes medications, lithium, and aspirin.

Additionally, if you're on any drug that's metabolized by the CYP2E1 enzyme pathway, mention this supplement to your pharmacist so they can verify it won't raise your drug levels.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence behind its ingredients' uses. Moderate medication interactions have been identified, and safety information is well characterized.

This onion extract may be worth considering if you're interested in its possibly effective use for scarring, but the evidence for other purposes is weak or missing. If you take blood thinners, diabetes drugs, lithium, or aspirin, you need to check with your pharmacist first — the interaction risks are real.

Anyone with a history of onion allergy should avoid it entirely.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Sep 25, 2020.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Onion, straight from the product label.

Brand Herbal Terra
Barcode (UPC) 7429524829851
Net contents 4 Fluid Ounce(s); 120 mL
Market status On market
Date entered into DSLD Sep 25, 2020
DSLD ID 234071
Product type Botanical
Supplement form Liquid
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Organic, Gluten Free, Sugar Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Onion by Herbal Terra, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 mL
Maximum serving Sizes:
1 mL
Servings per container
120
UPC/BARCODE
7429524829851
IngredientAmount% DV
certified organic Onion dried bulb liquid extract970 mg--

Other ingredients: Menstruum

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Suggested/Recommended/Usage/Directions

Direction Shake well before use. Adults take up to 30 drops (1 mL, one full squeeze of the dropper bulb) in 3-4 fl. oz of juice or water up to 4 times a day. We recommend to seek expert medical advice before taking this or any other herbal supplements.

FDA Disclaimer Statement

Notice This product has not been evaluated by the FDA and is not intended to diagnose, treat, cure, or prevent any disease.

Formulation

Manufactured in the USA in an FDA registered facility

Sugar free

Dried herb/menstruum ratio: 1:3 Expertly extracted Laboratory tested 330 mg/1 mL Premium product Super concentrated liquid herbal extract

Non GMO

No artificial ingredients, GMO, gluten, color additives, fillers, preservatives or binders. Natural Gluten Free

Precautions

Caution May have contraindications.

Do not use if you are allergic to any ingredients.

Consult a physician before using during pregnancy, if nursing, or if you are on any medications.

Keep out of the reach of children.

Storage

Store in a cool, dry, dark place.

Formula

Allium cepa

FDA Statement of Identity

Herbal Supplement

Seals/Symbols

Made in USA Made in an FDA registered facility Natural Gluten Free

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Onion by Herbal Terra label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Onion label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Onion by Herbal Terra

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 mL Dosage formLiquid Servings per container120 Amounts shown are per serving.

Certified organic Onion dried bulb liquid extract

Interacts with
275 drugs
970 mg per serving

Onion is a common food with a long history in traditional medicine, and it contains antioxidants like quercetin and sulfur compounds. Eating onion as...

Certified organic Onion dried bulb liquid extract monograph & interactions

Other (inactive) ingredients: Menstruum. These complete the product’s ingredient list but are not active constituents.

Interaction report

Onion by Herbal Terra Drug Interactions

Want to check YOUR meds against Onion?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
275Drugs
275 Moderate

Ingredients driving the most interactions

certified organic Onion dried bulb liquid extract 275

Individual Drug Interactions

The ingredients in Onion interact with 275 drugs. Click any drug to see the details.

1 of the 1 ingredient in Onion interact with drugs. Each result below shows which ingredient is responsible. certified organic Onion dried bulb liquid extract

Each ingredient & the kinds of drugs it affects

For each ingredient in Onion with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

certified organic Onion dried bulb liquid extract5 drug types · 275 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, concomitant use of anticoagulant or antiplatelet drugs with onion might increase the risk of bleeding.
In vitro research shows that onion inhibits platelet aggregation.

Likelihood Possible Evidence D
Antidiabetes Drugs

Concomitant use of antidiabetes drugs with onion may increase the risk of hypoglycemia.
Animal research and clinical research shows that taking onion can lower blood glucose levels. Monitor blood glucose levels closely.

Likelihood Possible Evidence B
Aspirin

Concomitant use of aspirin with onion may worsen onion allergy.
In one case report, a patient with a mild onion allergy reported worsening allergy, including swelling and severe urticaria, after taking aspirin.

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

Theoretically, taking onion might increase the levels and clinical effects of drugs metabolized by CYP2E1.
Animal research shows that taking onion powder inhibits CYP2E1. However, this interaction has not been reported in humans.

Likelihood Possible Evidence B
Lithium

Onion is thought to have diuretic properties. Theoretically, due to these potential diuretic effects, onion might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.

Likelihood Probable Evidence D
certified organic Onion dried bulb liquid extract full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Onion, from the product label.

Herbal Terra

See all Herbal Terra products
Name
Herbal Terra
Pharmacist Counseling Corner

Onion by Herbal Terra: Common Questions

Does Onion by Herbal Terra interact with any medications?
Yes. Based on its ingredients, Onion has a known interaction with 275 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Onion contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
What is this onion extract actually used for?
The evidence supports that it's possibly effective for scarring. For obesity, the research suggests it's probably not helpful. For other conditions like hair loss, chest pain, and clogged arteries, we just don't have enough reliable data to know either way.
Can I take this if I'm on a blood thinner like warfarin?
Not without talking to your pharmacist first. Onion can inhibit platelet aggregation — the process that helps your blood clot — which could raise your bleeding risk when combined with blood thinners. Your pharmacist may need to monitor you more closely or adjust your dose.
What are the most common side effects?
If you take it by mouth, abdominal pain and heartburn are the most common complaints. Most people tolerate onion well overall, but stomach distress from onion powder tends to be temporary.
Is it safe to take this if I'm pregnant or breastfeeding?
There isn't enough data on concentrated onion supplement doses during pregnancy and lactation to know either way. Talk with your doctor or pharmacist for personalized advice before using it.
Can onion allergy be serious?
Yes — although onion allergy is rare, there are reports of severe reactions including anaphylaxis, throat closing, and even migraines triggered by onion smell. If you have any history of onion sensitivity, avoid this supplement.
What's in the bottle besides onion?
The extract uses a menstruum — a liquid solvent — to concentrate the onion's compounds. That's the only other ingredient listed.

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

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Onion label
Go deeper

The Full Monographs Behind Onion’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Onion

Interacts with 275 drugs

Onion is a common food with a long history in traditional medicine, and it contains antioxidants like quercetin and sulfur compounds. Eating onion as part of a balanced diet is safe for most...

Read the full Onion monograph →
Sources

Sources & How We Checked

Onion's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 26 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Onion 26 references
  1. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  2. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  3. Bruynzeel DP. Bulb dermatitis. Dermatological problems in the flower bulb industries. Contact Dermatitis 1997;37:70-7.
  4. Eberhard P, Gall HM, Muller I, Moller R. Dramatic augmentation of a food allergy by acetylsalicylic acid. J Allergy Clin Immunol 2000;105:844 PubMed
  5. Teyssier, C., Amiot, M. J., Mondy, N., Auger, J., Kahane, R., and Siess, M. H. Effect of onion consumption by rats on hepatic drug-metabolizing enzymes. Food Chem.Toxicol. 2001;39(10):981-987. PubMed
  6. Moneret-Vautrin, D. A., Morisset, M., Lemerdy, P., Croizier, A., and Kanny, G. Food allergy and IgE sensitization caused by spices: CICBAA data (based on 589 cases of food allergy). Allerg.Immunol.(Paris) 2002;34(4):135-140.
  7. van Ketel, W. G. and de Haan, P. Occupational eczema from garlic and onion. Contact Dermatitis 1978;4(1):53-54. PubMed
  8. Mathew, P. T. and Augusti, K. T. Hypoglycaemic effects of onion, Allium cepa Linn. on diabetes mellitus - a preliminary report. Indian J.Physiol Pharmacol. 1975;19(4):213-217.
  9. Campos, K. E., Diniz, Y. S., Cataneo, A. C., Faine, L. A., Alves, M. J., and Novelli, E. L. Hypoglycaemic and antioxidant effects of onion, Allium cepa: dietary onion addition, antioxidant activity and hypoglycaemic effects on diabetic rats. Int J Food S
  10. Bajaj, J. S., Shaker, R., and Hogan, W. J. Esophageal veggie spasms: a food-specific cause of chest distress. Am.J Gastroenterol. 2004;99(7):1396-1398. PubMed
  11. El Demerdash, F. M., Yousef, M. I., and El Naga, N. I. Biochemical study on the hypoglycemic effects of onion and garlic in alloxan-induced diabetic rats. Food Chem.Toxicol. 2005;43(1):57-63. PubMed
  12. Hubbard, G. P., Wolffram, S., de Vos, R., Bovy, A., Gibbins, J. M., and Lovegrove, J. A. Ingestion of onion soup high in quercetin inhibits platelet aggregation and essential components of the collagen-stimulated platelet activation pathway in man: a pil
  13. Kook, S., Kim, G. H., and Choi, K. The antidiabetic effect of onion and garlic in experimental diabetic rats: meta-analysis. J Med Food 2009;12(3):552-560. PubMed
  14. Sharma, K. K., Gupta, R. K., Gupta, S., and Samuel, K. C. Antihyperglycemic effect of onion: effect on fasting blood sugar and induced hyperglycemia in man. Indian J.Med.Res. 1977;65(3):422-429.
  15. Jain, R. C., Vyas, C. R., and Mahatma, O. P. Letter: Hypoglycaemic action of onion and garlic. Lancet 12-29-1973;2(7844):1491.
  16. Jain, R. C. and Vyas, C. R. Letter: Hypoglycaemia action of onion on rabbits. Br.Med.J. 6-29-1974;2(5921):730. PubMed
  17. Veien, N. K., Hattel, T., Justesen, O., and Norholm, A. Causes of eczema in the food industry. Derm.Beruf.Umwelt. 1983;31(3):84-86.
  18. Tjokroprawiro, A., Pikir, B. S., Budhiarta, A. A., Pranawa, Soewondo, H., Donosepoetro, M., Budhianto, F. X., Wibowo, J. A., Tanuwidjaja, S. J., Pangemanan, M., and . Metabolic effects of onion and green beans on diabetic patients. Tohoku J Exp Med 1983; PubMed
  19. Brenner, S. and Wolf, R. Possible nutritional factors in induced pemphigus. Dermatology 1994;189(4):337-339. PubMed
  20. Roussos AP, Hirsch AR. Alliaceous migraines. Headache 2014;54(2):378-82. PubMed
  21. Akash MS, Rehman K, Chen S. Spice plant Allium cepa: dietary supplement for treatment of type 2 diabetes mellitus. Nutrition 2014;30(10):1128-37. PubMed
  22. Ebrahimi-Mamaghani M, Saghafi-Asl M, Pirouzpanah S, Asghari-Jafarabadi M. Effects of raw red onion consumption on metabolic features in overweight or obese women with polycystic ovary syndrome: a randomized controlled clinical trial. J Obstet Gynaecol Res PubMed
  23. Eldin IM, Ahmed EM, HM AE. Preliminary study of the clinical hypoglycemic effects of Allium cepa (red onion) in type 1 and type 2 diabetic patients. Environmental health insights 2010;4:71. PubMed
  24. Albanesi M, Pasculli C, Giliberti L, et al. Immunological characterization of onion (Allium cepa) allergy. Postepy Dermatol Alergol. 2019;36(1):98-103. PubMed
  25. Armentia A, Martín-Armentia S, Pineda F, et al. Allergic hypersensitivity to garlic and onion in children and adults. Allergol Immunopathol (Madr). 2019. pii: S0301-0546(19)30091-6. PubMed
  26. Nishimura M, Muro T, Kobori M, Nishihira J. Effect of daily ingestion of quercetin-rich onion powder for 12 weeks on visceral fat: A randomised, double-Blind, placebo-controlled, parallel-group study. Nutrients. 2019 Dec 28;12(1):91. PubMed

See these in context on the Onion monograph →

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

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