Osha Root
Ligusticum porteri
Also known as: Bear Root, Colorado Cough Root, Porter's Lovage
Overview
A high-elevation herb of the Rocky Mountains and northern Mexico, used for generations by Native American and Hispanic healers for colds, coughs, sore throat, and altitude sickness. Laboratory studies have found anti-inflammatory and antioxidant activity in the root, but osha has never been tested in a human clinical trial, and no study has tested it as a bronchodilator or against any virus. It is also slow-growing and considered at-risk in the wild, and it closely resembles poison hemlock — so sourcing matters.
Proposed mechanism
Contains phthalides — mainly Z-ligustilide, Z-butylidenephthalide, and diligustilide — plus ferulic acid. Laboratory and animal studies report antioxidant and immune-modulating activity in human white blood cells, gastroprotective effects in rats, and spasmolytic (smooth-muscle-relaxing) activity for some of its phthalides; a 1995 in vitro test of isolated ligustilide found only weak antiviral and antimicrobial activity. None of that work tested airway tissue, and no human studies have evaluated osha root for bronchodilation, antiviral effects, or lymphatic drainage from lung tissue. These remain traditional uses, not established mechanisms.
Mechanisms describe how researchers think a compound may act, often from laboratory work — a proposed mechanism is not proof of a clinical effect in people.
Traditional & studied uses
Related pathways
Pathway tags are a research aid for browsing the glossary — they are not a claim that this ingredient treats any condition.