Other Name(s):

Acide Usnique, Barba de Capuchino, Barbe de Jupiter, Barbe de Saint Antoine, Beard Moss, Mousse d'Arbre, Musgo de los Arboles, Old Man's Beard, Sodium Usniate, Tree Moss, Tree's Dandruff, Usnea barbata, Usnea florida, Usnea hirta, Usnea Lichen, Usnea plicata, Usnée, Usnée Barbue, Usnée Fleurie, Usniate de Sodium, Usnic Acid, Woman's Long Hair.


Usnea is a type of lichen that grows on trees. Though lichens appear to be single plants, they are really a combination of fungus and algae that grow together for their mutual benefit. Lichens grow in colorful, flat patches. Usnea may be whitish, reddish, or black. The plant body of usnea is used to make medicine.

Usnea is used for weight loss, pain relief, fever control, and wound healing; and to make phlegm easier to cough up.

Usnea is also used directly on the skin for sore mouth and throat.

Don't confuse usnea with oak moss (Evernia prunastri). Both usnea and oak moss are sometimes referred to as tree moss.

How does it work?

Usnea contains ingredients that are thought to fight germs that might cause infections. It also might decrease inflammation, pain, and fever.

Uses & Effectiveness

Insufficient Evidence to Rate Effectiveness for...

  • Human papilloma virus (HPV) infection. Early research suggests that applying a specific product (Zeta N, Bergamon Italia) containing zinc sulfate and usnic acid (a chemical found in usnea) to the vagina before and after surgical removal of HPV sores improves healing and reduces the recurrence of HPV infection for up to 6 months after surgery.
  • Weight loss.
  • Pain.
  • Fever.
  • Mild swelling (inflammation) of the mouth and throat.
  • Other conditions.
More evidence is needed to rate the effectiveness of usnea for these uses.

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).


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Side Effects

Usnea is POSSIBLY SAFE when used on the skin, though allergic reactions can occur.

Taking usnea by mouth is POSSIBLY UNSAFE. The sodium usniate (usnic acid) that usnea contains might cause liver damage. Sodium usniate is an ingredient of the brand named product LipoKinetix, which is marketed for weight loss. There were numerous cases of liver damage in people taking LipoKinetix. Symptoms, including nausea, weakness and fatigue, abdominal pain, and yellowing of the skin, usually develop from 2 weeks to 3 months after starting LipoKinetix. Symptoms disappear when it is discontinued. Additionally, there was one case of liver failure from taking pure usnic acid by mouth. Avoid taking usnea, LipoKinetix, or any other supplements containing usnea by mouth.

Special Precautions & Warnings

Pregnancy and breast-feeding: There is not enough reliable information about the safety of taking usnea if you are pregnant or breast-feeding. Stay on the safe side and avoid use.

Liver disease: Usnea contains some chemicals that might harm the liver. If you have liver disease, don't take usnea by mouth.


The appropriate dose of usnea depends on several factors such as the user's age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for usnea. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.


Vijayan, P., Raghu, C., Ashok, G., Dhanaraj, S. A., and Suresh, B. Antiviral activity of medicinal plants of Nilgiris. Indian J Med Res 2004;120(1):24-29. View abstract.

Aalto-Korte, K., Lauerma, A., and Alanko, K. Occupational allergic contact dermatitis from lichens in present-day Finland. Contact Dermatitis 2005;52(1):36-38. View abstract.

Abo-Khatwa AN, al-Robai AA, al-Jawhari DA. Lichen acids as uncouplers of oxidative phosphorylation of mouse-liver mitochondria. Nat Toxins 1996;4:96-102. View abstract.

al-Bekairi AM, Qureshi S, Chaudhry MA, et al. Mitodepressive, clastogenic and biochemical effects of (+)-usnic acid in mice. J Ethnopharmacol 1991;33:217-20. View abstract.

Arneborn, P., Jansson, A., and Bottiger, Y. [Acute hepatitis in a woman after intake of slimming pills bought via Internet]. Lakartidningen 7-11-2005;102(28-29):2071-2072. View abstract.

Behera, B. C., Verma, N., Sonone, A., and Makhija, U. Antioxidant and antibacterial activities of lichen Usnea ghattensis in vitro. Biotechnol Lett 2005;27(14):991-995. View abstract.

Behera, B. C., Verma, N., Sonone, A., and Makhija, U. Evaluation of antioxidant potential of the cultured mycobiont of a lichen Usnea ghattensis. Phytother.Res 2005;19(1):58-64. View abstract.

Bezivin, C., Tomasi, S., Rouaud, I., Delcros, J. G., and Boustie, J. Cytotoxic activity of compounds from the lichen: Cladonia convoluta. Planta Med 2004;70(9):874-877. View abstract.

Bian, X., Jin, J., Ding, D., and Zhang, H. [Study on the scavenging action of polysaccharide of Usnea longissima to oxygen radical and its anti-lipi peroxidation effects]. Zhong.Yao Cai. 2002;25(3):188-189. View abstract.

Bucar, F., Schneider, I., Ogmundsdottir, H., and Ingolfsdottir, K. Anti-proliferative lichen compounds with inhibitory activity on 12(S)-HETE production in human platelets. Phytomedicine 2004;11(7-8):602-606. View abstract.

Campanella, L., Delfini, M., Ercole, P., Iacoangeli, A., and Risuleo, G. Molecular characterization and action of usnic acid: a drug that inhibits proliferation of mouse polyomavirus in vitro and whose main target is RNA transcription. Biochimie 2002;84(4):329-334. View abstract.

Caviglia, A. M., Nicora, P., Giordani, P., Brunialti, G., and Modenesi, P. Oxidative stress and usnic acid content in Parmelia caperata and Parmelia soredians (Lichenes). Farmaco 2001;56(5-7):379-382. View abstract.

Choudhary, M. I., Azizuddin, Jalil, S., and Atta, ur Rahman. Bioactive phenolic compounds from a medicinal lichen, Usnea longissima. Phytochemistry 2005;66(19):2346-2350. View abstract.

Cocchietto, M., Skert, N., Nimis, P. L., and Sava, G. A review on usnic acid, an interesting natural compound. Naturwissenschaften 2002;89(4):137-146. View abstract.

Czetsch-Lindenwald, H., Moese, J., Konigsbauer, H., and Jurka, J. [Usnic acid as an antibiotic.]. Wien.Med Wochenschr. 12-24-1955;105(51-52):1063-1067. View abstract.

De Carvalho, E. A., Andrade, P. P., Silva, N. H., Pereira, E. C., and Figueiredo, R. C. Effect of usnic acid from the lichen Cladonia substellata on Trypanosoma cruzi in vitro: an ultrastructural study. Micron. 2005;36(2):155-161. View abstract.

Dobrescu D, Tanasescu M, Mezdrea A, et al. Contributions to the complex study of some lichens-Usnea genus. Pharmacological studies on Usnea barbata and Usnea hirta species. Rom J Physiol 1993;30:101-7. View abstract.

Durazo, F. A., Lassman, C., Han, S. H., Saab, S., Lee, N. P., Kawano, M., Saggi, B., Gordon, S., Farmer, D. G., Yersiz, H., Goldstein, R. L., Ghobrial, M., and Busuttil, R. W. Fulminant liver failure due to usnic acid for weight loss. Am.J Gastroenterol. 2004;99(5):950-952. View abstract.

Favreau JT, Ryu Ml, Braunstein G, et al. Severe hepatotoxicity associated with the dietary supplement LipoKinetix. Ann Intern Med 2002;136:590-5.

Figurska, E. H. and Jablonski, L. [Sensitivity of Staphylococcus and Streptococcus strains to usnic acid as compared to their sensitivity to antibiotics]. Med Dosw.Mikrobiol. 1976;28(1):9-12. View abstract.

Fournet, A., Ferreira, M. E., Rojas, de Arias, Torres, de Ortiz, Inchausti, A., Yaluff, G., Quilhot, W., Fernandez, E., and Hidalgo, M. E. Activity of compounds isolated from Chilean lichens against experimental cutaneous leishmaniasis. Comp Biochem Physiol C.Pharmacol Toxicol Endocrinol. 1997;116(1):51-54. View abstract.

Garcia, Rowe J., Garcia, Gimenez, and Saenz Rodriguez, M. T. Some lichen products have antimicrobial activity. Z Naturforsch.[C.] 1999;54(7-8):605-609. View abstract.

Garty, J., Kauppi, M., and Kauppi, A. The Influence of Air Pollution on the Concentration of Airborne Elementsand on the Production of Stress-Ethylene in the Lichen Usnea hirta(L.) Weber em. Mot. Transplanted in Urban Sites in Oulu, N. Finland. Arch Environ.Contam Toxicol. 1997;32(3):285-290. View abstract.

Ghione, M., Parrello, D., and Grasso, L. Usnic acid revisited, its activity on oral flora. Chemioterapia. 1988;7(5):302-305. View abstract.

Halici, M., Odabasoglu, F., Suleyman, H., Cakir, A., Aslan, A., and Bayir, Y. Effects of water extract of Usnea longissima on antioxidant enzyme activity and mucosal damage caused by indomethacin in rats. Phytomedicine 2005;12(9):656-662. View abstract.

Han, D., Matsumaru, K., Rettori, D., and Kaplowitz, N. Usnic acid-induced necrosis of cultured mouse hepatocytes: inhibition of mitochondrial function and oxidative stress. Biochem.Pharmacol. 2-1-2004;67(3):439-451. View abstract.

Hassal, C. H. The antibacterial activity of usnic acid and related compounds. Experientia 12-15-1950;6(12):462-464. View abstract.

Heine, A. and Tarnick, M. [Allergic contact eczema caused by usnic acid in deoderant sprays]. Dermatol Monatsschr. 1987;173(4):221-225. View abstract.

Hsu, L. M., Huang, Y. S., Chang, F. Y., and Lee, S. D. 'Fat burner' herb, usnic Acid, induced acute hepatitis in a family. J Gastroenterol.Hepatol. 2005;20(7):1138-1139. View abstract.

Ingolfsdottir K. Usnic acid. Phytochemistry 2002;61:729-36. View abstract.

Jin, J., Dong, Y., and He, L. [The study on skin wound healing promoting action of sodium usnic acid]. Zhong.Yao Cai. 2005;28(2):109-111. View abstract.

Johnson, R. B., Feldott, G., and Lardy, H. A. The mode of action of the antibiotic, usnic acid. Arch Biochem. 1950;28(3):317-323. View abstract.

Kathirgamanathar, S., Williams, D. E., Andersen, R. J., Bombuwela, K., De Silva, D., and Karunaratne, V. Beta-orcinol depsidones from the lichen Usnea sp. from Sri Lanka. Nat Prod Res 2005;19(7):695-701. View abstract.

Kilpo, O. [Antibacterial effects of an usnic acid derivative, usno, and its clinical uses with cases of pyoderma.]. Nord.Hyg.Tidskr. 1956;37(11-12):289-294. View abstract.

Klosa, J. [A new lichenic antibiotic.]. Pharmazie 1950;5(6):289-290. View abstract.

Konigsbauer, H. [The treatment of bacterial skin diseases with usnic acid.]. Hautarzt 1955;6(11):501-504. View abstract.

Krishna, D. R. and Venkataramana, D. Pharmacokinetics of D(+)-usnic acid in rabbits after intravenous and oral administration. Drug Metab Dispos. 1992;20(6):909-911. View abstract.

Krishna, D. R., Ramana, D. V., and Mamidi, N. V. In vitro protein binding and tissue distribution of D(+) usnic acid. Drug Metabol.Drug Interact. 1995;12(1):53-63. View abstract.

Kristmundsdottir, T., Jonsdottir, E., Ogmundsdottir, H. M., and Ingolfsdottir, K. Solubilization of poorly soluble lichen metabolites for biological testing on cell lines. Eur J Pharm Sci 2005;24(5):539-543. View abstract.

Kumar, K. C. and Muller, K. Lichen metabolites. 1. Inhibitory action against leukotriene B4 biosynthesis by a non-redox mechanism. J Nat Prod 1999;62(6):817-820. View abstract.

Kumar, K. C. and Muller, K. Lichen metabolites. 2. Antiproliferative and cytotoxic activity of gyrophoric, usnic, and diffractaic acid on human keratinocyte growth. J Nat Prod 1999;62(6):821-823. View abstract.

Lauterwein M, Oethinger M, Belsner K, et al. In vitro activities of the lichen secondary metabolites vulpinic acid, (+)-usnic acid, and (-)-usnic acid against aerobic and anaerobic microorganisms. Antimicrob Agents Chemother 1995;39:2541-3. View abstract.

Lee, K. A. and Kim, M. S. Antiplatelet and antithrombotic activities of methanol extract of Usnea longissima. Phytother Res 2005;19(12):1061-1064. View abstract.

Mayer, M., O'Neill, M. A., Murray, K. E., Santos-Magalhaes, N. S., Carneiro-Leao, A. M., Thompson, A. M., and Appleyard, V. C. Usnic acid: a non-genotoxic compound with anti-cancer properties. Anticancer Drugs 2005;16(8):805-809. View abstract.

Mitchell, J. C. Allergy to lichens. Allergic contact dermatitis from usnic acid produced by lichenized fungi. Arch Dermatol 1965;92(2):142-146. View abstract.

Miura, Y., Nakamura, Y., and Matsudaira, H. [The mode of action of usnic acid against bacteria.]. Bull.Soc.Chim.Biol (Paris) 1951;33(10):1577-1583. View abstract.

Neff, G. W., Reddy, K. R., Durazo, F. A., Meyer, D., Marrero, R., and Kaplowitz, N. Severe hepatotoxicity associated with the use of weight loss diet supplements containing ma huang or usnic acid. J Hepatol. 2004;41(6):1062-1064. View abstract.

Odabasoglu, F., Aslan, A., Cakir, A., Suleyman, H., Karagoz, Y., Halici, M., and Bayir, Y. Comparison of antioxidant activity and phenolic content of three lichen species. Phytother Res 2004;18(11):938-941. View abstract.

Odabasoglu, F., Cakir, A., Suleyman, H., Aslan, A., Bayir, Y., Halici, M., and Kazaz, C. Gastroprotective and antioxidant effects of usnic acid on indomethacin-induced gastric ulcer in rats. J Ethnopharmacol 1-3-2006;103(1):59-65. View abstract.

Okuyama, E., Umeyama, K., Yamazaki, M., Kinoshita, Y., and Yamamoto, Y. Usnic acid and diffractaic acid as analgesic and antipyretic components of Usnea diffracta. Planta Med 1995;61(2):113-115. View abstract.

Periera, E. C., Nascimento, S. C., Lima, R. C., Silva, N. H., Oliveira, A. F., Bandeira, E., Boitard, M., Beriel, H., Vicente, C., and Legaz, M. E. Analysis of Usnea fasciata crude extracts with antineoplastic activity. Tokai J Exp.Clin.Med 1994;19(1-2):47-52. View abstract.

Piorkowski, G. [Usnic acid as an oral antivirotic.]. Ther.Ggw. 1957;96(8):286-287. View abstract.

Pramyothin, P., Janthasoot, W., Pongnimitprasert, N., Phrukudom, S., and Ruangrungsi, N. Hepatotoxic effect of (+)usnic acid from Usnea siamensis Wainio in rats, isolated rat hepatocytes and isolated rat liver mitochondria. J Ethnopharmacol. 2004;90(2-3):381-387. View abstract.

Proksa, B. and Proksova, A. [Preparation and antineoplastic activity of acylhydrazones of R- and S-usnic acid]. Ceska.Slov.Farm 1999;48(5):233-236. View abstract.

Rademaker, M. Allergy to lichen acids in a fragrance. Australas.J Dermatol. 2000;41(1):50-51. View abstract.

Rafanelli, S., Bacchilega, R., Stanganelli, I., and Rafanelli, A. Contact dermatitis from usnic acid in vaginal ovules. Contact Dermatitis 1995;33(4):271-272. View abstract.

Ribeiro-Costa, R. M., Alves, A. J., Santos, N. P., Nascimento, S. C., Goncalves, E. C., Silva, N. H., Honda, N. K., and Santos-Magalhaes, N. S. In vitro and in vivo properties of usnic acid encapsulated into PLGA-microspheres. J Microencapsul. 2004;21(4):371-384. View abstract.

Rowe, J. G., Saenz, M. T., Garcia, M. D., and Gil, A. M. [Additional contribution to the study of the antimicrobial activity and identification of lichenic substances in some lichens from southern Spain]. Ann Pharm Fr 1991;49(5):278-285. View abstract.

Saenz, M. T., Garcia, M. D., and Rowe, J. G. Antimicrobial activity and phytochemical studies of some lichens from south of Spain. Fitoterapia 2006;77(3):156-159. View abstract.

Sanchez, W., Maple, J. T., Burgart, L. J., and Kamath, P. S. Severe hepatotoxicity associated with use of a dietary supplement containing usnic acid. Mayo Clin Proc 2006;81(4):541-544. View abstract.

Scirpa, P., Scambia, G., Masciullo, V., Battaglia, F., Foti, E., Lopez, R., Villa, P., Malecore, M., and Mancuso, S. [A zinc sulfate and usnic acid preparation used as post-surgical adjuvant therapy in genital lesions by Human Papillomavirus]. Minerva Ginecol. 1999;51(6):255-260. View abstract.

Shibamoto, T. and Wei, C. I. Mutagenicity of lichen constituents. Environ Mutagen. 1984;6(5):757-762. View abstract.

Shkliar, I. I. [Treatment of trichomoniasis in men with antibiotics-sodium salt of usnic acid]. Vestn.Dermatol Venerol. 1968;42(4):89-91. View abstract.

Takai, M., Uehara, Y., and Beisler, J. A. Usnic acid derivatives as potential antineoplastic agents. J Med Chem. 1979;22(11):1380-1384. View abstract.

Venkataramana, D. and Krishna, D. R. Pharmacokinetics of d(+)-usnic acid in rabbits after intravenous administration. Eur J Drug Metab Pharmacokinet. 1993;18(2):161-163. View abstract.

Vijayakumar, C. S., Viswanathan, S., Reddy, M. K., Parvathavarthini, S., Kundu, A. B., and Sukumar, E. Anti-inflammatory activity of (+)-usnic acid. Fitoterapia 2000;71(5):564-566. View abstract.

Wang, X. P., Liu, H. J., Zhen, L., Zhou, Z. T., Li, M. Y., and Zhang, W. D. [Plasmid elimination effect of usnic acid on antibiotic-resistant Staphylococcus aureus]. Zhong.Yao Cai. 2006;29(1):36-39. View abstract.

Wu, J., Zhang, M., Ding, D., Tan, T., and Yan, B. [Effect of Cladonia alpestris on Trichomonas vaginalis in vitro]. Zhongguo Ji.Sheng Chong.Xue.Yu Ji.Sheng Chong.Bing.Za Zhi. 1995;13(2):126-129. View abstract.

Yamamoto, Y., MIURA, Y., Kinoshita, Y., Higuchi, M., Yamada, Y., Murakami, A., Ohigashi, H., and Koshimizu, K. Screening of tissue cultures and thalli of lichens and some of their active constituents for inhibition of tumor promoter-induced Epstein-Barr virus activation. Chem Pharm Bull (Tokyo) 1995;43(8):1388-1390. View abstract.

Yilmaz, M., Turk, A. O., Tay, T., and Kivanc, M. The antimicrobial activity of extracts of the lichen Cladonia foliacea and its (-)-usnic acid, atranorin, and fumarprotocetraric acid constituents. Z.Naturforsch.[C.] 2004;59(3-4):249-254. View abstract.

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