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Male Fern

Medically reviewed by Last updated on Feb 20, 2020.

Scientific Name(s): Dryopteris filix-mas (L.) Schott, Dryopteris marginalis (L)
Common Name(s): Aspidium, Bear's paw, Knotty brake, Male fern, Marginal fern, Shield fern, Worm fern

Clinical Overview


D. filix-mas has been used as a traditional vermifuge. Investigations into potential applications of related species, particularly Dryopteris crassirhizoma and Dracaena fragrans, report antioxidant and antimicrobial activity, but no clinical trials support these claims.


Clinical evidence does not support specific doses of male fern, and toxicities have been reported with traditional doses.


Male fern extract is potentially toxic.


Avoid use. Information regarding safety and efficacy in pregnancy and lactation is lacking.


None well documented. Traditional use of male fern extract combined with castor oil increases absorption of the extract, resulting in enhanced toxicity.

Adverse Reactions

Adverse reactions associated with traditional doses have included headache, dyspnea, nausea, diarrhea, vertigo, tremors, convulsions, and cardiac and respiratory failure. Impaired vision and jaundice have also been reported.


Male fern extract is potentially toxic.

Scientific Family

  • Dryopteridaceae
  • Polypodiaceae (wood fern)


D. filix-mas is a hardy, ornamental fern with semievergreen leaves that can grow up to 1 m in length. Stalks are scaly and pale brown and each leaf grows from the root base. Its rhizomes and frond bases are used medicinally. The plant grows throughout the United States in dry terrain, in rich woods, and on rocky slopes. Originally thought to be the male plant of Athyrium filix-femina (female fern), it was given the name "filix-mas."Franchi 1988, Khan 2009, Step 1905, USDA 2015


Male fern has been used in traditional medicine as a vermifuge ("worm fern"), with the early Greeks and Romans also recognizing the plant’s value in destroying or expelling parasitic worms.Franchi 1988 In Chinese medicine, the extract has been used to treat wounds, recurrent nosebleeds, and heavy menstrual bleeding. The components of the plant have also been used as veterinary vermifuges. D. Filix-mas formerly listed in the United States Pharmacopeia (USP).Khan 2009


Major constituents of Dryopteris ferns include flavonoids and terpenoids.Cao 2013, Han 2015 Male fern contains approximately 6% to 15% of an oleoresin, which contains several chemical constituents including filicins (filicic/filixic acid, albaspidin, flavaspidic acid), aspidinol, alkanes, triterpene hydrocarbons, lignins, volatile oils, and resins.Franchi 1988, Khan 2009 Margaspidin, para-aspidin, phloraspin, and other constituents have also been described.Han 2015, Khan 2009

Uses and Pharmacology


Animal data

Filicin and filmarone are active vermifuges, particularly toxic to tapeworms.Duke 2002, Khan 2009

Clinical Data

An older clinical study examined the anthelmintic effects of male fern administered via intubation as compared with the effects of piperazine.Goodwin 1958 Another study examined male fern's anthelmintic properties using the plant's encapsulated extract in combination with a pretreatment of magnesium sulfate solution.Mello 1978

Other Effects

Antioxidant, antimicrobial, and chemotherapeutic properties of related fern species, particularly D. crassirhizoma and D. fragrans, have been investigated.Cao 2013, Gao 2015, Han 2015, Huang 2014, Jiang 2013, Kwon 2007, Lee 2008, Lu 2012, Magalhães 2010, Mazzio 2009, Sun 2013, Xie 2015, Zhang 2012, Zhao 2014


Clinical evidence does not support specific doses of male fern. Traditional dosage of the plant as an anthelmintic was 5 to 8 g oleoresin extract; however, adverse effects at this dosage have been documented.Duke 2002

Pregnancy / Lactation

Avoid use. Information regarding safety and efficacy in pregnancy and lactation is lacking.


None well documented. Traditional use of male fern extract combined with castor oil increases absorption of the extract, resulting in enhanced toxicity.Khan 2009

Adverse Reactions

Therapeutic doses have been associated with adverse events,Duke 2002, Hargreaves 1966, Khan 2009 including headache, dyspnea, nausea, diarrhea, vertigo, tremors, convulsions, and cardiac and respiratory failure.Khan 2009 Impaired vision and jaundice have also been reported.Duke 2002, Hargreaves 1966


Male fern extract is potentially toxic,Duke 2002, Hargreaves 1966, Khan 2009 and references in the USP have been removed.Franchi 1988, Khan 2009 Some consumer websites reference a 1976 German report of penis enlargement in rats with the use of D. filix-mas extract, but the effect has not been explained or further elucidated.Kantemir 1976


Cao J, Xia X, Chen X, Xiao J, Wang Q. Characterization of flavonoids from Dryopteris erythrosora and evaluation of their antioxidant, anticancer and acetylcholinesterase inhibition activities. Food Chem Toxicol. 2013;51:242-250.2306359410.1016/j.fct.2012.09.039
Dryopteris filix-mas L. USDA, NRCS. 2015. The PLANTS Database (, 18 December 2015). National Plant Data Team, Greensboro, NC 27401-4901 USA.
Duke J, Bogenschutz-Godwin M, duCellier J, Duke P. Handbook of Medicinal Herbs. 2nd ed. Boca Raton, FL: CRC Press; 2002.
Franchi GG, Ferri S. Localization of the active principles of the male fern (Dryopteris filix-mas (L.) Schott.) by fluorescence microscopy. Pharmacol Res Commun. 1988;20(suppl 5):135-138.3247342
Gao C, Guo N, Li N, et al. Investigation of antibacterial activity of aspidin BB against Propionibacterium acnes [published online November 23, 2015]. Arch Dermatol Res.2659657610.1007/s00403-015-1603-x
Goodwin LG, Standen OD. Piperazine and male fern in expulsion of tapeworms. Br Med J. 1958;1(5063):133-134.13489333
Han X, Li Z, Li CY, Jia WN, Wang HT, Wang CH. Phytochemical constituents and biological activities of plants from the genus Dryopteris. Chem Biodivers. 2015;12(8):1131-1162.2626556710.1002/cbdv.201400157
Hargreaves T. The effect of male fern extract on biliary secretion. Br J Pharmacol Chemother. 1966;26(1):34-40.5950680
Huang YH, Zeng WM, Li GY, et al. Characterization of a new sesquiterpene and antifungal activities of chemical constituents from Dryopteris fragrans (L.) Schott. Molecules. 2014;19(1):507-513.2445124610.3390/molecules19010507
Jiang B, Chi C, Fu YW, Zhang QZ, Wang GX. In vivo anthelmintic effect of flavonol rhamnosides from Dryopteris crassirhizoma against Dactylogyrus intermedius in goldfish (Carassius auratus). Parasitol Res. 2013;112(12):4097-4104.2401334210.1007/s00436-013-3600-3
Kantemir I, Akder G, Tulunay O. Preliminary report on an unexpected effect of an extract from Dryopteris filix mas (author's transl) [in German]. Arzneimittelforschung. 1976;26(2):261-262.947210
Khan IA, Abourashed EA. Leung's Encyclopedia of Common Natural Ingredients Used in Food, Drugs, and Cosmetics. 3rd ed. Hoboken, NJ: Wiley; 2009.
Kwon DY, Kang OH, Choi JG, et al. Antibacterial effect of Dryopteris crassirhizoma against methicillin-resistant Staphylococcus aureus. Fitoterapia. 2007;78(6):430-433.17590531
Lee JS, Miyashiro H, Nakamura N, Hattori M. Two new triterpenes from the Rhizome of Dryopteris crassirhizoma, and inhibitory activities of its constituents on human immunodeficiency virus-1 protease. Chem Pharm Bull (Tokyo). 2008;56(5):711-714.18451564
Lu C, Zhang HY, Ji J, Wang GX. In vivo anthelmintic activity of Dryopteris crassirhizoma, Kochia scoparia, and Polygala tenuifolia against Dactylogyrus intermedius (Monogenea) in goldfish (Carassius auratus). Parasitol Res. 2012;110(3):1085-1090.2184238110.1007/s00436-011-2592-0
Magalhães LG, Kapadia GJ, da Silva Tonuci LR, et al. In vitro schistosomicidal effects of some phloroglucinol derivatives from Dryopteris species against Schistosoma mansoni adult worms. Parasitol Res. 2010;106(2):395-401.1989886910.1007/s00436-009-1674-8
Mazzio EA, Soliman KF. In vitro screening for the tumoricidal properties of international medicinal herbs. Phytother Res. 2009;23(3):385-398.1884425610.1002/ptr.2636
Mello EB, Vilela MP, Maugé GC, Malheiro DM. Oral treatment of human taeniasis by ethereal extract of male-fern (aspidium) preceded by the administration of hypertonic solution of magnesium sulphate. Zentralbl Bakteriol Orig A. 1978;241(3):384-387.569412
Step E. Wayside and Woodland Blossoms: A Pocket Guide to British Wild Flowers for the Country Rambler. London, England: Warne; 1905.
Sun Y, Mu F, Li C, et al. Aspidin BB, a phloroglucinol derivative, induces cell cycle arrest and apoptosis in human ovarian HO-8910 cells. Chem Biol Interact. 2013;204(2):88-97.2362850810.1016/j.cbi.2013.04.008
Xie Y, Zheng Y, Dai X, Wang Q, Cao J, Xiao J. Seasonal dynamics of total flavonoid contents and antioxidant activity of Dryopteris erythrosora. Food Chem. 2015;186:113-118.2597679910.1016/j.foodchem.2014.05.024
Zhang Y, Luo M, Zu Y, et al. Dryofragin, a phloroglucinol derivative, induces apoptosis in human breast cancer MCF-7 cells through ROS-mediated mitochondrial pathway. Chem Biol Interact. 2012;199(2):129-136.2279632310.1016/j.cbi.2012.06.007
Zhao DD, Zhao QS, Liu L, et al. Compounds from Dryopteris fragrans (L.) Schott with cytotoxic activity. Molecules. 2014;19(3):3345-3355.2464703510.3390/molecules19033345


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