Uva ursi, also called bearberry, is a traditional folk remedy that has been used by Native Americans for hundreds of years, primarily for bladder and urinary tract infections. In small doses for short periods of time, uva ursi preparations are generally considered safe. However, in larger doses, uva ursi can be toxic and lead to liver damage. Consult with your doctor and a professional herbalist or naturopath before you take uva ursi in any form.
Uva ursi is an evergreen shrub native to alpine forests in North America, Europe, Siberia and the Himalayas. Uva ursi produces small, sour red berries that are a favorite of many bear species, which accounts for its nickname. However, the berries are not used for medicinal purposes; rather, the leaves of the uva ursi shrub are the primary component of herbal preparations. The leaves are usually crushed into a fine powder and put in capsules, but the leaves can also be soaked in hot water to produce an herbal infusion.
The leaves of the uva ursi shrub contain a variety of phytochemicals that display antioxidant and antimicrobial properties, particularly compounds called arbutin and hydroquinone, according to "Principles and Practice of Phytotherapy: Modern Herbal Medicine." These properties are helpful in fighting infections and minimizing tissue damage, and they explain why uva ursi has been used by traditional healers for infections of the bladder and the urinary tract. Uva ursi leaves also contain tannins, which are strongly astringent and help to reduce inflammation. Before any recommendations can be made, the effects of uva ursi on people with genitourinary infections need to be properly researched.
Hydroquinone, a component of uva ursi leaves, is toxic in large doses and can cause serious liver damage, according to the University of Maryland Medical Center. Because of this, uva ursi should be taken only for short periods of time not exceeding five days, and on no more than five separate occasions over the course of a year. The recommended adult dosage is between two and five milligrams of the dried herb daily for up to five days. Children should not be given uva ursi under any circumstances. Others who should not take uva ursi include women who are pregnant or breastfeeding, and people with hypertension, Crohn's disease, stomach ulcers, digestive problems, kidney problems or liver disease.
Negative side effects from the ingestion of uva ursi are generally mild and include nausea, vomiting, irritability and insomnia. Symptoms of liver damage include yellowing of the skin and eyes, a condition called jaundice, and elevated liver enzymes that are detectable with a blood test. Contact your doctor if you experience any negative side effects after consuming uva ursi.