Beard lichen

What it is used for

• Bacterial infections

  Limited

  Used as an antiseptic in US and Spanish folk medicine. Extracts are strongly active in the lab against Gram-positive bacteria such as Staphylococcus aureus and Mycobacterium tuberculosis, less so against Gram-negative bacteria and yeasts.^2,5

• Fungal skin and nail infections

  Limited

  Sixty-five cases of athlete's foot (tinea pedis) improved with topical usnic acid in an older report; extracts show moderate activity against dermatophytes in the lab.^3,2

• Sore throat

  Traditional

  The German Commission E monograph recommends Usnea for mild inflammation of the oral and pharyngeal mucosa; this rests on traditional use and lab antibacterial data rather than trials.¹

• Mouth ulcers and gum health

  Traditional

  Part of the same Commission E indication; usnic acid has been used in toothpaste and mouthwash, and experimental oral films contain far less usnic acid than oral supplements did.^1,3,4

• Wounds and cuts

  Traditional

  Used on wounds in South African folk medicine; no clinical studies found.¹

• Fever

  Traditional

  Usnea species are used in Asia, Africa and Europe for pain relief and fever control.¹

• Cough

  Traditional

  Recorded in European folk medicine for whooping cough, along with insomnia, bleeding, nausea and jaundice.⁵

How it is prepared

Amounts are as recorded by the named source, not a recommendation.

Safety

In the healing traditions

• Ancient Greek medicine

  Usnea

  Hippocrates is said to have used it for urinary complaints.

• European folk medicine

  Old man's beard

  Antiseptic in Spain; for whooping cough, insomnia, bleeding, nausea and jaundice elsewhere in Europe.

• Western herbalism

  Usnea

  Antiseptic in North American folk use; German Commission E approval for mild inflammation of mouth and throat.

• African traditional medicine

  Usnea

  Applied to wounds in South African folk medicine.

Active compounds

usnic acid

dibenzofuran lichen acid, first isolated in 1844; antibacterial against Gram-positive organisms; hepatotoxic in concentrated oral doses, interfering with liver mitochondria in mice

History

Usnic acid was first isolated in 1844 and is the most studied lichen compound. In the early 2000s it was sold in the United States in 'fat burner' supplements, which led to an FDA warning in 2001 and to liver transplants in young adults.

Sources

1. 1.Zugic A et al. Evaluation of anticancer and antioxidant activity of a commercially available CO2 supercritical extract of old man's beard (Usnea barbata). PLoS One 2016
2. 2.Sepahvand A et al. Usnea sp.: antimicrobial potential, bioactive compounds, ethnopharmacological uses and other pharmacological properties; a review article. J Ethnopharmacol 2021 (abstract)
3. 3.Avigan MI, Mozersky RP, Seeff LB. Scientific and regulatory perspectives in herbal and dietary supplement associated hepatotoxicity in the United States. Int J Mol Sci 2016
4. 4.Popovici V et al. Formulation and development of bioadhesive oral films containing Usnea barbata dry ethanol extract. Pharmaceutics 2022
5. 5.Popovici V et al. Elemental analysis and in vitro evaluation of antibacterial and antifungal activities of Usnea barbata from Călimani Mountains, Romania. Plants 2021
6. 6.Guo L et al. Review of usnic acid and Usnea barbata toxicity. J Environ Sci Health C 2008 (abstract)
7. 7.Durazo FA et al. Fulminant liver failure due to usnic acid for weight loss. Am J Gastroenterol 2004 (abstract)
8. 8.Sanchez W et al. Severe hepatotoxicity associated with use of a dietary supplement containing usnic acid. Mayo Clin Proc 2006 (abstract)
9. 9.Araújo AA et al. Review of the biological properties and toxicity of usnic acid. Nat Prod Res 2015 (abstract)

Reference, not prescription. Nothing here is medical advice. Herbs can interact with medicines and be dangerous in pregnancy; tell your doctor or pharmacist about anything you take.