Limited evidenceGut health

Ajwain (Carom Seed)

A carminative Indian spice used for bloating and indigestion. One randomized trial of a three-oil blend containing ajwain outperformed omeprazole in functional dyspepsia, but ajwain alone has never been tested.

Evidence last reviewed: August 2026

What the science says

Part of one positive dyspepsia trial Limited evidence
In a randomized double-blind trial, a soft-gel capsule of Zataria multiflora, Anethum graveolens and Trachyspermum ammi essential oils produced higher response rates than omeprazole 20 mg over two weeks in roughly 45 patients with functional dyspepsia. Ajwain was one of three oils, so its own contribution is unknown.
Antimicrobial activity in the laboratory only Limited evidence
Laboratory work shows ajwain essential oil inhibits drug-resistant gastrointestinal pathogens and their biofilms, and potentiates ampicillin in vitro. Nothing of this has been tested in people.

Dosage & safety

Studied doseCulinary use is a pinch to about 1 g of seed with meals. The dyspepsia trial used 180 mg of combined essential oils twice daily; there is no established ajwain-only supplement dose.

SafetyThymol-rich ajwain oil irritates the stomach and is toxic in overdose — never take undiluted essential oil. Avoid in pregnancy, where the seed has traditional emmenagogue use, and in active peptic ulcer disease.

Scientific references

Comparison of a Novel Herbal Medicine and Omeprazole in the Treatment of Functional Dyspepsia: A Randomized Double-Blinded Clinical Trial
Bordbar G, Miri MB, Omidi M — Gastroenterol Res Pract, 2020
Antibacterial, antibiofilm, and gene expression assessment of ajwain (Trachyspermum ammi) essential oil on drug-resistant gastrointestinal pathogens and its combination effect with ampicillin
Ozma MA, Alileh NF, Abbasi A — Lett Appl Microbiol, 2025

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