Synopsis

Source of validity: Traditional
Rating (out of 5): 2

Lichens have been used traditionally in various cultures for the treatment of respiratory ailments, including colds. Species such as Usnea (commonly called "Old Man’s Beard") and Cetraria islandica (Iceland moss) have a long history of use in European, North American, and Asian herbal medicine. Historically, decoctions and syrups prepared from these lichens were administered to soothe sore throats, suppress coughs, and alleviate symptoms of upper respiratory tract infections. The purported benefits are attributed primarily to their mucilaginous content, which can coat and soothe mucous membranes, and to secondary metabolites such as usnic acid, which have demonstrated antimicrobial properties in vitro. However, scientific validation for the antiviral efficacy of lichens specifically against viruses that cause the common cold (mainly rhinoviruses and coronaviruses) is limited. Some studies have indicated mild antibacterial, antifungal, or general antimicrobial activity from lichen extracts, but robust clinical trials confirming benefit against viral respiratory infections are lacking. Most available evidence is based on traditional use and laboratory studies, not human clinical trials. Thus, while lichens have a strong tradition of use for respiratory complaints, their direct antiviral effect against cold viruses is not well supported by current scientific research.

More about Lichen (unspecified)
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Other ingredients used for Colds (antiviral)

Other health conditions supported by Lichen (unspecified)

Products containing Lichen (unspecified)