FWD 2 Expanded Commission E: Fennel seed

Herbal Medicine: Expanded Commission E

Fennel seed

Latin Name: Foeniculum vulgare
Pharmacopeial Name: Foeniculi fructus
Other Names: bitter fennel, common fennel


Fennel is a tall perennial herb native tothe Mediterranean region, now widely cultivated as an annual or perennial in Bulgaria, Romania, Hungary, Greece, Turkey, Italy, France, Germany, Egypt, India, and China (Bruneton, 1995;Grieve, 1979;Leung and Foster, 1996; Wichtl and Bisset, 1994).Fennel is one of Germany's more important medicinal plant crops (Lange and Schippmann, 1997).The material of commerce comes mainly fromBulgaria, Hungary, Romania, Egypt, and China (BHP, 1996; Wichtl and Bisset, 1994).

Its modern therapeutic uses in Germany and the United States stem from traditional Greek medicine as practiced by Hippocrates and later by Dioscorides. It is still widely used in traditional Arabian medicine as a diuretic, appetizer, and digestive (Tanira et al., 1996). Its original Greek genus name was Marathron, from maraino, meaning to grow thin. Its current genus name, Foeniculum, was assigned by the Romans, derived from the Latin word foenum, meaning hay (Grieve, 1979).Fennel's therapeutic uses have been introduced and integrated into many other systems of traditional medicine, includingAyurvedic, Chinese, and Japanese Kampo. For example, the present Ayurvedic Pharmacopoeia recommends it in dried fruit or fluidextract form, for flatulent dyspepsia, anorexia, and flatulent colic in children (Karnick, 1994). Its indications for use in the present Chinese pharmacopoeia include for distending pain in the epigastrium with anorexia, dysmenorrhea with lower abdominal pain and cold sensation, vomiting, and diarrhea (Tu, 1992).

The modern therapeutic applications for fennel seed and oil are supportable based on theirhistory of use in well-established systems of traditional medicine, phytochemical investigations, and in vitro and in vivo studies in animals.

In Germany, fennel seed is licensed as a standard medicinal tea for dyspepsia. It is also used in cough syrups and honeys (antitussives and expectorants), and stomach and bowel remedies, especially in pediatrics, as aqueous infusion, water (Aqua Foeniculi), drage (lozenge), juice, and syrup. It is often used in combination with aniseed (Leung and Foster, 1996; Wichtl and Bisset, 1994).In the United States,it is also used as a component of galactagogue preparations. Indications for use of fennel oil are similar to those for fennel seed. In Germany and the United States, fennel oil is used as an expectorant component of cough remedies, and also as a carminative component of stomach and bowel remedies in dosage forms including honey and syrup. Traditionally, it is combined with laxative or purgative herbs to counteract or modify their harsh griping effects in the bowels (ESCOP, 1997; Leung and Foster, 1996; Nadkarni, 1976; Wichtl and Bisset, 1994). The Commission E limits the use of fennel seed and fennel oil for up to two weeks and then recommends consulting a physician.

Pharmacopeial grade bitter fennel seed must contain not less than 4% (v/m)total volatile oils, calculated with reference to the anhydrous drug, as determined by the European Pharmacopoeia (Ph.Eur.3) method 2.8.12. Its volatile oil must be composed of not less than 60% anethole, not less than 15% fenchone, and maximum 5% estragole, as determined by Ph.Eur.3 GC method 2.2.28 (DAB 10, 1991; ESCOP, 1997; Ph.Eur.3, 1997). The Austrian Pharmacopoeia requires not less than 3.5% volatile oil ( AB, 19811983).

The official fennel oil of the European Pharmacopoeia is derived from bitter fennel (var. vulgare) as opposed to sweet fennel (var. dulce). Pharmacopeial grade fennel oil must be composed of not less than 60% anethole, not less than 15% fenchone, and no more than 5% estragole, as determined by Ph.Eur.3 GC method 2.2.28 (Ph.Eur.3, 1997).The relative proportions of its main constituents determine its overall bitterness or sweetness. Fenchone has a disagreeable bitter taste; anethole is sweet (Bown, 1995; Grieve, 1979). The relative ratios of these components and their yields vary somewhat by strain and region. Historically, the strains yielding oils most suitable for pharmaceutical use have been Russian, Saxon, Galician, and Romanian (Bown, 1995; Grieve, 1979; Nadkarni, 1976). As the ratio of its main components determine the pharmaceutical quality of the oil, long-term studies investigated the productionthe biological and structural regularities of essential oil accumulation in developing fruits of bitter fennel. In a study of 13 different plant populations, representing three different chemovarieties (e.g., cv. 'Soroks ri'), the presence and ratio of anethole, methyl-chavicol, and fenchonewere analyzed and found to be stable throughout nine stages of flowering and fruiting (Bern th et al., 1998).


Fennel seed consists of the dried, ripe fruits of Foeniculum vulgare Miller var. vulgare (Miller) Thellung [Fam. Apiaceae] and their preparations in effective dosage. The seeds contain at least 4% essential oil with not more than 5% estragole.

Chemistry and Pharmacology

Fennel seed contains essential oils (46%), of which 5070% is trans-anethole, 922% (+)-fenchone, 25% estragole (methyl chavicol), plus a- and b-pinene, a-phellandrene, limonene, camphene, and others; fixed oil (1720%), of which 6075% is petroselinic acid; the flavonoids kaempferol, quercetin, isoquercitrin, and rutin; protein (1620%); minerals (relatively high in calcium and potassium); sugars; and vitamins (Bruneton, 1995; ESCOP, 1997; Leung and Foster, 1996; Wichtl and Bissett, 1994).

The Commission E reported that fennel seed promotes gastrointestinal motility and in higher concentrations acts as an antispasmodic. In experiments, anethole and fenchone have been shown to have a secretolytic action in the respiratory tract. In the frog, aqueous fennel extracts raise the mucociliary activity of the ciliary epithelium.

The British Herbal Pharmacopoeia reported its action as carminative (BHP, 1996). Aqueous infusion of bitter fennel seed increased the transport velocity of the isolated ciliated epithelium of a frog esophagus by 12% (ESCOP, 1997; Leung and Foster, 1996; M ller-Limmroth and Frhlich, 1980). Fennel administered orally increased the spontaneous movement of the unanesthetized rabbit stomach and taken intravenously reduced the inhibition of stomach movement by sodium pentobarbitone (Niiho et al., 1977). A bitter fennel infusion reduced spasms induced by acetylcholine and barium chloride in vitro in isolated guinea pig ileum and inhibited in situ ileum spasms in vivo in cats (ESCOP, 1997).


The Commission E approved the internal use of fennel seed preparations for dyspepsias such as mild, spastic gastrointestinal afflictions, fullness, and flatulence. It is also approved for catarrh of the upper respiratory tract. Fennel syrup and fennel honey are used for catarrh of the upper respiratory tract in children.

In France, fennel seed is allowed the same indications for use as the star anise seed or aniseed (Bruneton, 1995). The German Standard License for infusion of fennel seed reports its use against flatulence and cramp-like pains in the gastrointestinal tract, especially in infants and small children, and to dissolve mucus in the respiratory tract (Braun et al., 1997). ESCOP lists fennel seed for dyspeptic complaints such as mild, spasmodic gastrointestinal complaints, bloating, and flatulence, for catarrh of the upper respiratory tract, and fennel syrup or fennel honey for catarrh of the upper respiratory tract in children (ESCOP, 1997).


Herb for infusions and preparations containing an equivalent amount of the essential oil: None known.

Other preparations: Pregnancy.

Side Effects

In individual cases allergic reactions of skin and respiratory tract.

Use During Pregnancy and Lactation

No restrictions known for the seed used in infusions and preparations containing an equivalent amount of the essential oil. Other fennel seed preparations not recommended during pregnancy. No restrictions known during lactation.

Interactions with Other Drugs

None known.

Dosage and Administration

Unless otherwise prescribed: 5-7 g per day crushed or ground seeds for teas, tea-like products, and other galenical preparations for internal use.

Fennel syrup or honey: 10-20 g (Erg.B.6).

Compound fennel tincture: 5-7.5 g (=5-7.5 ml).

Equivalent preparations:

Infusion: 1-3 g in 150 ml water, two to three times daily between meals.

Fluidextract 1:1 (g/ml): 1-3 ml, two to three times daily between meals.

Tincture 1:5 (g/ml): 5-15 ml, two to three times daily between meals.

Native dry extract 3.9-4.9:1 (w/w): 0.2-0.7 g, two to three times daily between meals.

Duration of administration: Fennel preparations should not be used on a prolonged basis (several weeks) without consulting a physician or pharmacist.

Note: Fennel syrup, fennel honey: Diabetics must consider sugar content of bread exchange units according to manufacturer's information.


Bern th, J. et al. 1998. Production-biological and structural regularities of essential oil accumulation in developing fruits of fennel (Foeniculum vulgare Mill.). Budapest: UHFI Department of Medicinal Plant Production.

Bown, D. 1995. Encyclopedia of Herbs and Their Uses. New York: DK Publishing, Inc. 283284.

Braun, R. et al. 1997. Standardzulassungen f r FertigarzneimittelText and Kommentar. Stuttgart: Deutscher Apotheker Verlag.

British Herbal Pharmacopoeia (BHP). 1996. Exeter, U.K.: British Herbal Medicine Association.

Bruneton, J. 1995. Pharmacognosy, Phytochemistry, Medicinal Plants. Paris: Lavoisier Publishing.

Deutsches Arzneibuch, 10th ed. (DAB 10). 1991. (With subsequent supplements through 1996.) Stuttgart: Deutscher Apotheker Verlag.

ESCOP. 1997. 'Foeniculi aetheroleum' and 'Foeniculi fructus.' Monographs on the Medicinal Uses of Plant Drugs. Exeter, U.K.: European Scientific Cooperative on Phytotherapy.

Europäisches Arzneibuch, 3rd ed. (Ph.Eur.3). 1997. Stuttgart: Deutscher Apotheker Verlag. 939-941.

Grieve, M. 1979. A Modern Herbal. New York: Dover Publications, Inc.

Karnick, C.R. 1994. Pharmacopoeial Standards of Herbal Plants, Vols. 12. Delhi: Sri Satguru Publications. Vol. 1:139141; Vol. 2:71.

Lange, D. and U. Schippmann. 1997. Trade Survey of Medicinal Plants in GermanyA Contribution to International Plant Species Conservation. Bonn: Bundesamt f r Naturschutz. 3233.

Leung, A.Y. and S. Foster. 1996. Encyclopedia of Common Natural Ingredients Used in Food, Drugs, and Cosmetics, 2nd ed. New York: John Wiley & Sons, Inc.

M ller-Limmroth, W. and H.H. Frhlich. 1980. Wirkungsnachweis einiger phytotherapeutischer Expektorantien auf den mukoziliaren Transport [Proof of efficacy of some phytotherapeutic expectorants on mucociliary transport]. Fortschr Med 98:95101.

Nadkarni, K.M. 1976. Indian Materia Medica. Bombay: Popular Prakashan. 557559.

Niiho, Y., I. Takayanagi, K. Takagi. 1977. Effects of a combined stomachic and its ingredients on rabbit stomach motility in situ. Jpn J Pharmacol 27:177179.

Ph.Eur.3. See Europäisches Arzneibuch.

sterreichisches Arzneibuch, Vols. 12, 1st suppl. ( AB). 19811983. Wien: Verlag der sterreichischen Staatsdruckerei.

Tanira, M.O.M. et al. 1996. Pharmacological and toxicological investigations on Foeniculum vulgare dried fruit extract in experimental animals. Phytother Res 10:3336.

Tu, G. (ed.). 1992. Pharmacopoeia of the People's Republic of China (English Edition 1992). Beijing: Guangdong Science and Technology Press. 70.

Wichtl, M. and N.G. Bisset (eds.). 1994. Herbal Drugs and Phytopharmaceuticals. Stuttgart: Medpharm Scientific Publishers.

Additional Resources

Betts, T.J. 1968. Anethole and fenchone in the developing fruits of Foeniculum vulgare Mill. J Pharm Pharmacol 20(6):469472.

Boyd, E.M. and E.P. Sheppard. 1968. The effect of steam inhalation of volatile oils on the output and composition of respiratory tract fluid. J Pharmacol Exp Ther 163(1):250256.

. 1971. An autumn-enhanced mucotropic action of inhaled terpenes and related volatile agents. Pharmacology 6(2):6580.

Deutsches Arzneibuch, 10th ed. Vol. 16. (DAB 10). 1991. Kommentar. Stuttgart: Wissenschaftliche Verlagsgesellschaft mbH.

Food Chemicals Codex, 2nd ed.(FCC II).1972. Washington, D.C.: National Academy of Sciences.

Hnsel, R., K. Keller, H. Rimpler, G. Schneider (eds.). 1993. Hagers Handbuch der Pharmazeutischen Praxis, 5th ed. Vol. 5. Berlin-Heidelberg: Springer Verlag. 156-181.

Kapoor, L.D., A. Singh, S.L. Kapoor, S.N. Srivastava. 1969. Survey of Indian plants for saponins, alkaloids and flavonoids. Lloydia 32(3):297304.

Kapoor, L.D. 1990. Handbook of Ayurvedic Medicinal Plants. Boca Raton: CRC Press. 189.

List, P.H. and L. Hrhammer (eds.). 19731979. Hagers Handbuch der Pharmazeutischen Praxis, Vols. 17. New York: Springer Verlag.

Madaus, G. 1976. Lehrbuch der Biologischen Heilmittel. Vol. 2. Hildesheim; New York: Georg Olms. 13541361.

Marsh, A.C. et al. 1977. Composition of Foods, Spices, and Herbs: Raw, Processed, Prepared. Agriculture Handbook No. 82. Washington, D.C.: Agricultural Research Service, U.S. Department of Agriculture.

Maruzzella, J.C. and M. Freundlich. 1959. Antimicrobial substances from seeds. J Am Pharm Assoc 48:356358.

Maruzzella J.C. and N.A. Sicurella. 1960. Antibacterial activity of essential oil vapors. J Am Pharm Assoc 49:692694.

McGuffin, M., C. Hobbs, R. Upton, A. Goldberg. 1997. American Herbal Product Association's Botanical Safety Handbook. Boca Raton: CRC Press.

Pharmacope Franaise Xe dition (Ph.Fr.X.). 19831990. Moulins-les-Metz: Maisonneuve S.A.

Ramadan, F.M., R.T. el-Zanfaly, F.A. el-Wakeil, M. Alian. 1972. On the antibacterial effects of some essential oils. I. Use of agar diffusion method. Chem Mikrobiol Technol Lebensm 2:5155.

Reynolds, J.E.F. (ed.). 1993. Martindale: The Extra Pharmacopoeia, 30th ed. London: The Pharmaceutical Press. 13691370.

Steinegger, E. and R. Hnsel. 1992. Pharmakognosie, 5th ed. Berlin-Heidelberg: Springer Verlag.

Weiss, R.F. 1991. Lehrbuch der Phytotherapie, 7th ed. Stuttgart: Hippokrates. 107108.

Yen, K.Y. 1992. The Illustrated Chinese Materia MedicaCrude and Prepared. Taipei: SMC Publishing, Inc. 133.

This material was adapted from The Complete German Commission E MonographsTherapeutic Guide to Herbal Medicines. M. Blumenthal, W.R. Busse, A. Goldberg, J. Gruenwald, T. Hall, C.W. Riggins, R.S. Rister (eds.) S. Klein and R.S. Rister (trans.). 1998. Austin: American Botanical Council; Boston: Integrative Medicine Communications.

1) The Overview section is new information.

2) Description, Chemistry and Pharmacology, Uses, Contraindications, Side Effects, Interactions with Other Drugs, and Dosage sections have been drawn from the original work. Additional information has been added in some or all of these sections, as noted with references.

3) The dosage for equivalent preparations (tea infusion, fluidextract, and tincture) have been provided based on the following example:

  • Unless otherwise prescribed: 2 g per day of [powdered, crushed, cut or whole] [plant part]
  • Infusion: 2 g in 150 ml of water
  • Fluidextract 1:1 (g/ml): 2 ml
  • Tincture 1:5 (g/ml): 10 ml

4) The References and Additional Resources sections are new sections. Additional Resources are not cited in the monograph but are included for research purposes.

This monograph, published by the Commission E in 1994, was modified based on new scientific research. It contains more extensive pharmacological and therapeutic information taken directly from the Commission E.

Excerpt from Herbal Medicine: Expanded Commission E Monographs
Copyright 2000 American Botanical Council
Published by Integrative Medicine Communications
Available from the American Botanical Council.