Usnea barbata

Usnea barbata                                        Common name:  Old Man’s Beard, Tree lichen

Part used: Whole lichen (dried thallus)

Constituents:  Lichen acids (usnic acid and derivatives, diffractaic acid), polysaccharides, mucilage, anthraquinones (endocrocin), fatty acids (oleic, linolenic, arachadonic), all essential amino acids, vitamins, carotene.

Medicinal actions:  Antibiotic, anti-fungal, anti-parasitic, immuno-stimulating, immuno-regulator, demulcent, anti-tumor, expectorant, muscle relaxant

Medicinal use: Usnea is primarily antibiotic, especially against gram positive organisms such as:  Streptococcus, Staphylococcus, Mycobacterium tuberculosis and other fast-growing species.  Polysaccharides are immuno-stimulatory and can be used for local and systemic infections. Common conditions it is used for are sinusitis, acute/chronic lung infections, vaginal infections, and topically as a compress for open wounds to stop bleeding and infection.


  • Lichen acids, like usnic acid are antibiotic and anti-tumor. Disrupts bacterial cell membrane function, inhibits ATP formation and oxidative phosphorylation without effecting human cells. Inhibits and weakens the growth of TB bacillus, pneumonococcus, streptococci & staphylococci. Diffractaic acid is an analgesic.
  • Fatty acids & polysaccharides have anti-tumor effects.
  • Polysaccharides are immuno-stimulating.

Pharmacy: Up to 10 g/day powdered herb. Tincture: (1:6, 90%), 2-5 ml TID. Infusion: 2-3tsp/cup, TID. External application as tincture or compress. Lozenge: 100mg herb, 3-6x/day. Note: Dose short term up to 3 weeks.

Toxicity: No adverse effects expected. Topically, usnic acid may cause skin irritation.

Contraindications: None known.

Interactions: None known.

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