Principal Proposed Uses
Native to high altitudes in the Southwest and Rocky Mountain states, the root of the osha plant is a traditional Native American remedy for respiratory infections and digestive problems . A related plant, Ligusticum wallichii, has a long history of use in Chinese medicine, and most of the scientific studies on osha were actually performed on this species.
What Is Osha Used for Today?
Osha is frequently recommended for use at the first sign of a respiratory infection. Like a sauna, it will typically induce sweating, and according to folk wisdom this may help avert the development of a full-blown cold
. Osha is also taken during respiratory infections as a cough
suppressant and expectorant, hence the common name "Colorado cough root." However, there have not been any double-blind placebo-controlled studies
to verify these proposed uses. (For information on why double-blind studies are so important, see Why Does This Database Rely on Double-blind Studies?
), Chinese research suggests that Ligusticum wallichii can relax smooth muscle tissue (perhaps thereby moderating the cough reflex) and inhibit the growth of various bacteria. 1 Whether these findings apply to osha as well is unknown.
Like other bitter herbs, osha is said to improve symptoms of indigestion
and increase appetite.