Drug & supplement interaction

Onion + Felbamate

Felbamate brand name: Felbatol.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Onion and Felbamate in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

Onion and Felbamate

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Felbamate and Onion in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Onion safety at a glance

Onion overall Generally safe Onion as a food is generally safe for most people; concentrated supplements are less studied.
Pregnancy Use caution Food amounts are considered fine, but concentrated supplement doses are not well studied and should be avoided.
Breastfeeding Use caution Food amounts are likely fine, but there is not enough evidence on medicinal supplement doses.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Felbamate and Onion? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Felbamate

Interactions in our licensed database are recorded against drug classes, not just single drug names. Felbamate is filed under 8 classifications — including anticonvulsants, cytochrome p450 2c19 (cyp2c19) inhibitors, qt interval-prolonging drugs. Onion has documented interactions with 5 drug classes — the most serious being anticoagulant/antiplatelet drugs (moderate), antidiabetes drugs (moderate) and aspirin (moderate) — and none of Felbamate’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Onion Does Interact With Other Medications

Onion has 275 moderate known drug interactions in our database — Felbamate isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Onion

Covers the 2,830 medications we’ve checked against Onion. Pick one to open its full report.

What to actually watch for

No Interaction Found — But Data Suggests Onion and Felbamate May Share Several of the Same Side Effects

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do. One of them is worth acting on rather than waiting out — marked below.

  • A severe allergic reaction Worth acting on Additional detail

    Onion

    “Allergy to onion is rare, although there are reports of symptoms to both oral and topical exposure. In one case, oral exposure or the aroma of onions caused the sensation of throat closing in an allergic woman. In a 35-year-old man, cooked onion ingestion triggered anaphylaxis. In another case, the smell of onion was identified as a trigger for migraines in a 32-year-old female.”

    Onion · Natural Medicines adverse-effect record, reported in allergic rhinitis (hay fever).

    4 sources cited
    1. 41752. 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.
    2. 101743. 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
    3. 88404. Roussos AP, Hirsch AR. Alliaceous migraines. Headache 2014;54(2):378-82. PubMed
    4. 101742. Albanesi M, Pasculli C, Giliberti L, et al. Immunological characterization of onion (Allium cepa) allergy. Postepy Dermatol Alergol. 2019;36(1):98-103. PubMed

    Felbamate

    Listed in the ADVERSE REACTIONS section of the FDA label for Felbamate. Read the label on DailyMed ›

  • Heartburn Additional detail

    Onion

    “The consumption of large quantities of onions or onion powder can cause stomach distress or heartburn (18,95155,104772). Stomach distress from onion powder appears to be transient. In one case report, consumption of raw onions led to esophageal spasm.”

    Onion · Natural Medicines adverse-effect record, reported in dyspepsia.

    4 sources cited
    1. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
    2. 95155. 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
    3. 104772. 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
    4. 66841. 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

    Felbamate

    Listed in the ADVERSE REACTIONS section of the FDA label for Felbamate. Read the label on DailyMed ›

  • Migraine Additional detail

    Onion

    Recorded for Onion in the same Natural Medicines adverse-effect record shown under A severe allergic reaction above.

    Felbamate

    Listed in the ADVERSE REACTIONS section of the FDA label for Felbamate. Read the label on DailyMed ›

  • Stomach pain Additional detail

    Onion

    Recorded for Onion in the same Natural Medicines adverse-effect record shown under A severe allergic reaction above.

    Felbamate

    Listed in the ADVERSE REACTIONS section of the FDA label for Felbamate. Read the label on DailyMed ›

Effects for Felbamate come from the ADVERSE REACTIONS section of its FDA label; effects for Onion come from the Natural Medicines adverse-effect record, quoted above. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Everything else you take

See Every Supplement That Interacts With Felbamate

This page covers Onion only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Felbamate page lists 172 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: 1,4-butanediol (major), Activated Charcoal (major), American Hellebore (major), Arsenic (major) and Beer (major).

By severity: 14 major · 141 moderate · 17 minor.

From our pharmacist’s overview on the Felbamate page

“Felbamate (Felbatol) is a seizure medicine usually reserved for epilepsy that other drugs have failed to control, in part because it can stress the liver on its own. That history is why its 172 supplement and herbal interactions deserve real vigilance, starting with the 14 rated major.”

Reviewed by 2 · Jul 18, 2026

Open the Felbamate interaction page

One more smart check

Taking Onion as Part of a Dietary Supplement Product? Check It for Interactions

We hold 1,061 real supplement products containing Onion, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Onion. Even though Onion itself has no known interaction with Felbamate, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Onion and Felbamate Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Onion
Top 25%

#247 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Felbamate
Top 25%

#315 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Onion reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Onion and Felbamate records this page draws on were last updated July 10, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Onion

What is Onion?

Onion
  • Colds and respiratory symptoms
  • Heart and cholesterol health
  • Blood sugar support
  • Antimicrobial and wound care
  • Scar appearance (topical gels)

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 people, but high-dose supplements have only limited human evidence for any specific health condition. Talk with your pharmacist or doctor before using concentrated onion products for a medical reason.

Allium cepa · Amaryllidaceae · Bulb (and sometimes the green leaves and extracted juice) · Fresh bulb, juice, dried powder, capsules, extracts, and topical gels

An interaction check asks whether these two react with each other — it does not ask whether Onion is a good idea for someone in your situation. Here is what our Onion record says about it on its own.

Onion: dosing

There is no official standardized dose of onion for any health condition. As a food, onion is simply eaten in normal cooking amounts. For supplements, gels, and extracts, the right amount depends on the specific product and how concentrated it is.If you choose to use an onion supplement, follow the directions on the product label and do not exceed the recommended amount.

From our Onion monograph — the full record covers uses, side effects and every documented interaction.

Read the full Onion monograph & all interactions
Medication

About Felbamate

What Is Felbamate Used For?

Brand name: Felbatol

Felbamate is not a first-line seizure medication. It is used only when a person's epilepsy has not responded well enough to other treatments and the seizures are severe enough that the serious risks of this drug are considered acceptable.

In adults, felbamate can be used alone or alongside other antiepileptic drugs (AEDs) to treat partial seizures (seizures that start in one part of the brain), with or without spreading to become a full seizure. In children, felbamate is used as an add-on treatment for both partial and generalized seizures linked to Lennox-Gastaut syndrome, a severe form of childhood epilepsy. Felbatol is specifically labeled for these uses in both adults and children.

See full Felbamate drug information
Keep checking

Other Drugs & Onion

Browse every other medication we’ve checked against Onion — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
275Moderate
0Minor
2,554No known interaction
Moderate

275 interactions

Showing 60 of 275 moderate interactions — see all 275 on the Onion page.

No interaction 2,554 drugs checked — show the list
Evidence & sources

Onion References

The 26 references that drive our Onion 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. 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.

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Onion and Felbamate Together: Common Questions

Is it safe to take Onion with Felbamate?
We do not list a known interaction between Onion and Felbamate. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
Do Onion and Felbamate have any of the same side effects?
Yes — our sources link each of them separately to 4 of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
How was the Onion and Felbamate combination checked?
Interactions in our licensed database are recorded against drug classes. Felbamate is filed under 8 classifications, and Onion has documented interactions with 5 drug classes — none of Felbamate's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Onion interact with any other medications?
Yes. Onion has 275 documented drug interactions in our database — Felbamate is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Felbamate interact with any supplements?
Yes. Felbamate has documented interactions with 172 supplements in our database — Onion is not one of them. The Felbamate interaction page linked on this page lists every one, ranked by severity.

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

Still Have a Question About Felbamate and Onion?

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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.