Osha, whose botanical name is Ligusticum porteri, is a plant native to the western United States and Mexico. A member of the Umbelliferae family, osha has been used for centuries by Native Americans and Mexicans as a treatment for sore throats, fevers, and influenza. The plant belongs to the same family as parsley and dill, and it has the same long thin hollow stalk with large divided leaves. These leaves can reach heights of 2 ft (0.6 m). Osha's seeds and flowers are at the top of the plant and
Osha root is a powerful antiviral and antibacterial agent, used for bronchial infections and sore throats. Taking a tincture or decoction of osha root, or chewing directly on the root, causes perspiration and enhances the body's immune function. Although osha has a bitter taste, its root has a numbing effect that soothes sore throats. Since it is also an expectorant, it is very useful for coughs and pharyngitis, and can also be used for very early stages of tonsillitis. Osha root tea helps with gastrointestinal discomfort, in particular indigestion and stomach upset associated with vomiting. It can be used to increase appetite. Both osha root tincture and tea can be used topically on cuts and scrapes, as osha also has strong antibacterial qualities. Michael Moore, a contemporary American herbalist associated with the Southwest School of Herbal Medicine, states that osha can be used for head colds with dry cough; certain stages of pharyngitis; early stages of tonsillitis; coughs; influenza with persistent coughing; dry, hot fevers; and acute brochial pneumonia. Osha can be given together with echinacea for leukocytosis.
Osha is available as whole or powdered dried roots. Dried osha root can be chewed directly. Michael Moore suggests taking a "walnut-sized root" every three to four hours. A cold infusion of osha, two to six ounces, can be taken as needed. Other products that contain osha come in different concentrations and should be mixed or diluted according to label instructions. If osha is used in tincture form, 20–60 drops can be taken up to five times a day. One part osha to two parts honey works well as a cough syrup, and is more appealing to children, who often dislike the plant's bitter taste.
The most important precaution to take with osha is correct identification. The plant is often confused with hemlock parsley, which it closely resembles. Osha is also sometimes mistaken for poison hemlock, which can be fatal to humans if ingested. Osha has also been detected in the milk of lactating mothers, and should not be used by women who are pregnant or nursing.
There are no known side effects with using osha other than allergy or hypersensitivity to it or to its plant family. High doses of osha taken over extended periods of time, however, may cause kidney or liver toxicity.
No known adverse reactions have been reported with osha.
Moore, Michael. Herbal Materia Medica. Southwest School of Herbal Medicine, n.d.
Moore, Michael. Herb/Medicine Contraindications. Southwest School of Herbal Medicine, 1995.
Moore, Michael. Medicinal Plants of the Mountain West. Santa Fe, NM: Museum of New Mexico Press, 1979.
Moore, Michael. Specific Indications for Herbs in General Use. Southwest School of Herbal Medicine, 1994.
Katherine Y. Kim