Limited evidenceGut health

Anise Seed

A sweet carminative seed. One well-conducted trial of enteric-coated anise oil improved IBS symptoms; beyond that, its use for indigestion and cramps rests on tradition.

Evidence last reviewed: August 2026

What the science says

Anise oil for IBS Limited evidence
A three-armed double-blind clinical trial of enteric-coated anise oil capsules reported superiority over both placebo and an active herbal comparator for IBS symptoms over four weeks. It is a single trial from one centre.
Recognised but unreplicated in systematic review Limited evidence
A systematic review of Western herbal medicines in IBS listed Pimpinella anisum oil among preparations showing efficacy in a rigorously designed trial, while stressing that outside peppermint, aloe and asafoetida no positive result had been replicated.

Dosage & safety

Studied doseThe IBS trial used 200 mg of enteric-coated anise oil three times daily for four weeks. As a tea, 1–3 g of crushed seed per cup.

SafetySafe as a food. Anethole has weak oestrogen-like activity, so use caution in hormone-sensitive conditions and avoid concentrated oil in pregnancy. Note that star anise is an unrelated plant and Japanese star anise is neurotoxic — do not substitute.

Scientific references

Efficacy and safety of enteric coated capsules of anise oil to treat irritable bowel syndrome
Mosaffa-Jahromi M, Lankarani KB, Pasalar M — J Ethnopharmacol, 2016
Western herbal medicines in the treatment of irritable bowel syndrome: A systematic review and meta-analysis
Hawrelak JA, Wohlmuth H, Pattinson M — Complement Ther Med, 2020

Where to buy

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