Usnea

Related Terms

Ab-Solution plus?, ascorbic acid, atranorin, barbatic acid, binan, depsides, depsidones, diffractaic acid, dihydrousnic acid, evernic acid, glutinol, isoanhydromethyldihydrousnic acid, isodihydrousnic acid, isolichenin, isomethoxide, lichen, Lipokinetix?, longissiminone A, longissiminone B, methylusnic acid, oak moss extract, old man's beard, parmeliaceae, raffinose, sodium usnate, sodium usnic acid, tree's dandruff, tree moss, woman's long hair, Usnea amblyoclada, Usnea barbata, Usnea complanta, Usnea dasypoga, Usnea diffracta, Usnea fasciata, Usnea florida, Usnea ghattensis, Usnea hirta, Usnea longissima, Usnea rubiginea, Usnea siamensis, Usnea subfloridana, Usneaceae (family), usnic acid, usno, Zeta-N?.

Background

Usnea species are classified as fruticose lichens, which are a symbiosis of fungus and algae. Usnea grows on the bark and wood of coniferous (e.g., spruces, firs, and pines) and deciduous hardwood (e.g., oak, hickory, walnut, apple, and other fruit trees) host trees throughout the northern hemisphere in Asia, Europe, and North America.
Usnea has been used as a therapeutic agent in traditional Chinese medicine (TCM) for thousands of years. Usnea longissima is traditionally taken by mouth for lung and upper respiratory infections, and applied on the skin to treat surface infections or external ulcers. It is still used today in TCM in liquid extract and tincture form to treat tuberculosis lymphadenitis.
Usnic acid is a secondary metabolite uniquely found in all lichens. Usnea or usnic acid has been used as a human papillomavirus (HPV) treatment and as an oral hygiene agent, with limited effectiveness.
Usnic acid is also found in various oral (by mouth) dietary supplements, including Lipokinetix?, marketed as a weight loss agent. However, Lipokinetix? may not be safe and may cause liver damage. Lipokinetix?, now withdrawn from the market, contained phenylpropanolamine (PPA), caffeine, yohimbine hydrochloride, diiodothyronine and usnic acid.

Evidence Table

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. GRADE *
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. GRADE *


Usnea and usnic acid both are reported in laboratory studies to have antiviral activity. A combination of usnic acid and zinc sulfate may help treat human papillomavirus. Additional study of usnea alone, and not in combination, is needed to a make a strong recommendation.

C


Usnea and usnic acid both are reported in laboratory studies to have antiviral activity. A combination of usnic acid and zinc sulfate may help treat human papillomavirus. Additional study of usnea alone, and not in combination, is needed to a make a strong recommendation.

C


Usnea has been used historically as an oral antibacterial agent, and animal and laboratory studies support this. However, there is currently insufficient available evidence to recommend for or against the use of mouthwashes or rinses containing usnea extracts or usnic acid for oral hygiene.

 C


Usnea has been used historically as an oral antibacterial agent, and animal and laboratory studies support this. However, there is currently insufficient available evidence to recommend for or against the use of mouthwashes or rinses containing usnea extracts or usnic acid for oral hygiene.

 C
* Key to grades

A: Strong scientific evidence for this use
B: Good scientific evidence for this use
C: Unclear scientific evidence for this use
D: Fair scientific evidence for this use (it may not work)
F: Strong scientific evidence against this use (it likley does not work)
* Key to grades

A: Strong scientific evidence for this use
B: Good scientific evidence for this use
C: Unclear scientific evidence for this use
D: Fair scientific evidence for this use (it may not work)
F: Strong scientific evidence against this use (it likley does not work)

Tradition / Theory

The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.

Dosing

Adults (18 years and older):
There is no proven safe or effective dose. However, the German Commission E has approved 1 usnea lozenge (equivalent of 100 milligrams powdered usnea lichen) 3-6 times daily for mouth irritation. Usnea has also been taken by mouth as a powder (100 milligrams three times a day), tea, or tincture (3-4 milliliters three times daily). Usnea has also been applied on the affected area(s) of the skin two or three times daily.

Safety

The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Interactions

Interactions with Drugs
Usnea may increase bleeding time by inhibition of platelet aggregation. Caution is advised in patients with bleeding disorders or taking drugs that may increase the risk of bleeding. Some examples of drugs that increase the risk of bleeding include aspirin, anticoagulants (blood thinners) such as warfarin (Coumadin?) or heparin, anti-platelet drugs such as clopidogrel (Plavix ?), and non-steroidal anti-inflammatory drugs such as ibuprofen (Motrin?, Advil?) or naproxen (Naprosyn?, Aleve?). Dosing adjustments may be necessary.
Usnea may interfere with the way the body processes certain drugs using the liver's "cytochrome P450" enzyme system. As a result, the levels of these drugs may be decreased in the blood, and reduce the intended effects. Patients taking any medications should check the package insert and speak with a qualified healthcare professional, including a pharmacist, about possible interactions.

Attribution

This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

Bibliography

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