Herb library · Spice · Foeniculum vulgare
Fennel
An anise-flavored plant of the carrot family whose seeds, leaves and bulb are all eaten. Fennel seed tea is an old remedy for wind and colic, including infant colic; the European Medicines Agency accepts it for adults on traditional grounds but advises against it under age 4, and trials in people are few and weak.
Traditional use
Fennel has been grown in European gardens for centuries; Culpeper recorded the custom of boiling it with fish. Seeds were taken for wind, cramps, coughs and to increase breast milk. In India the seed is a condiment and after-meal digestive (saunf); Dutt's 1877 compilation from Sanskrit medical works records that Hindu physicians used it mostly as an aromatic added to other medicines, and that distilled fennel water was sold as a household remedy for wind. In China the seeds are prescribed for colic and indigestion. Today fennel tea is widely sold for bloating, period cramps and colicky babies.
What studies show
- Insufficient
Bloating, wind, period cramps and coughs with a cold: the European Medicines Agency accepts fennel tea for these only on the basis of long traditional use, and concludes that the medicinal use of fennel fruit is not supported by adequate clinical evidence.
- Limited
Infant colic: a 2016 Cochrane review found low-quality evidence that herbal products (including a fennel seed oil emulsion and a fennel, chamomile and lemon balm mix) reduced crying time, and concluded that herbal agents cannot be recommended for infants with colic. EMA calls the evidence very preliminary.
- Limited
Period pain: a 2016 Cochrane review found no consistent evidence that fennel beat placebo and no clear difference from anti-inflammatory painkillers, from single small trials. A 2026 meta-analysis of Apiaceae seeds judged fennel and dill potentially useful alongside standard care, and called for better trials.
- Insufficient
Menopause symptoms: EMA reports that most small studies failed to show a significant effect of fennel compared with placebo.
- Limited
Breast milk supply: LactMed says two small studies found increases in some measures, such as milk volume and infant weight gain, but no rise in prolactin has been seen.
Be careful of
Cautions
- ConditionBabies and young children: EMA does not recommend fennel tea under age 4 for lack of adequate data, and for ages 4 to 12 only short-term and not if the daily estragole intake would exceed its guidance value. Fennel contains estragole, which caused liver tumors in mice; EMA says exposure of young children should be minimized.
- AmountKitchen amounts are not the same as medicinal teas and oils. EMA's adult tea dose is 1.5 g of seed in 250 ml of boiling water, three times a day, for no more than 2 weeks.
- AllergyAvoid if you are allergic to anise, caraway, celery, coriander, dill, carrots or other plants in this family, to anethole, or to mugwort pollen. Reactions can affect the skin or breathing, and photosensitivity has been reported.
- PregnancyEMA does not recommend fennel medicines in pregnancy or breastfeeding. LactMed notes heavy use of a nursing tea containing fennel and anise appeared to poison two breastfed newborns, and raised liver enzymes were reported in a woman drinking a tea that contains fennel.
- NoteFennel oil is generally recognized as safe as a food ingredient in the US, and fennel is generally well tolerated by adults.
- Ask a clinicianTalk with a clinician or pharmacist before using this if you take prescription medicines, are pregnant or breastfeeding, or are giving it to a child.
From the old books
What herbals and dispensaries of the past printed. History, in their words.
“Fennel seeds are largely used as a condiment. In medicine they are chiefly used as an aromatic adjunct to other articles. Distilled fennel water is prepared and sold in India, under the name of A'rak bádian, and is used as a domestic carminative.”
“One good old fashion is not yet left off, viz. to boil Fennel with fish; for it consumes that phlegmatic humour, which fish most plentifully afford and annoy the body with, though few that use it know wherefore they do it”
Sources
- European Union herbal monograph on Foeniculum vulgare Miller subsp. vulgare var. vulgare, fructus, Revision 1 (opens in a new tab) · EMA · read September 25, 2026
- European Union herbal monograph on Foeniculum vulgare Miller subsp. vulgare var. dulce (Mill.) Batt. & Trab., fructus, Revision 1 (opens in a new tab) · EMA · read September 25, 2026
- Assessment report on Foeniculum vulgare Miller, fructus (bitter and sweet), Revision 1 (EMA/HMPC/240553/2016) (opens in a new tab) · EMA · read September 25, 2026
- Public statement on the use of herbal medicinal products containing estragole (EMEA/HMPC/137212/2005) (opens in a new tab) · EMA · read September 25, 2026
- Fennel — Drugs and Lactation Database (LactMed), NCBI Bookshelf (opens in a new tab) · NIH · read September 25, 2026
- Pain-relieving agents for infantile colic (Cochrane Database Syst Rev, 2016) — PubMed record (opens in a new tab) · NIH · read September 25, 2026
- Dietary supplements for dysmenorrhoea (Cochrane Database Syst Rev, 2016) — PubMed record (opens in a new tab) · NIH · read September 25, 2026
- Efficacy of herbaceous Apiaceae plants in primary dysmenorrhea: a systematic review and meta-analysis of RCTs (Ann Pharm Fr, 2026) — PubMed record (opens in a new tab) · NIH · read September 25, 2026
Reviewed September 25, 2026.