Uva ursi (Arctostaphylos uva ursi), also known as bearberry because bears like eating the fruit, has been used medicinally since the 2nd century. Native Americans used it as a remedy for urinary tract infections. In fact, until the discovery of sulfa drugs and antibiotics, uva ursi was a common treatment for such bladder and related infections.
Through modern day scientific research in test tubes and animals, researchers have discovered that uva ursi's ability to fight infection are due to several chemicals, including arbutin and hydroquinone. The herb also contains tannins that have astringent effects, helping to shrink and tighten mucous membranes in the body. That, in turn, helps reduce inflammation and fight infection.
Today, uva ursi is sometimes used to treat urinary tract infections and cystitis (bladder inflammation). But uva ursi can be toxic: Hydroquinone, a component of uva ursi, can cause serious liver damage. Conventional medications that have fewer risks are available to treat urinary tract infections.
Researchers believe the herb works best when a person's urine is alkaline since acid destroys its antibacterial effect. Uva ursi works best at the first sign of infection. However, more research is needed to see if uva ursi works in humans.
Uva ursi is a trailing evergreen shrub that produces red berries and flourishes in alpine forests in many regions, including North America, Europe, the Iberian Peninsula, Siberia, and the Himalayas. It grows slowly but succeeds in places where other plants cannot, such as the walls of canyons. It has short, creeping, reddish brown branches and pink or white bell-shaped flowers that bloom in the summer, followed by clusters of berries. Bears are said to be fond of the shiny, bright red or pink fruit, which is edible but tastes sour.
Only the leaves -- not the berries -- are used in herbal medicine.
Uva ursi is commercially available as crushed leaf or powder preparations.
Do not give uva ursi to children.
Because uva ursi can be toxic, talk to your doctor before taking it. Recommended adult doses are:
Uva ursi should not be taken for more than 5 days at a time. (See "Precautions" section.)
The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, can trigger side effects and interact with other herbs, supplements, or medications. For these reasons, you should take herbs with care, under the supervision of a health care provider.
One of the chemicals in uva ursi, hydroquinone, can damage the liver. Uva ursi should be taken only for short periods -- no longer than 5 days -- under a health care provider's supervision. You shouldn't take a series of doses of uva ursi more than 5 times in 1 year. Do not take more than the recommended doses.
Reported side effects are generally mild and include nausea and vomiting, irritability, and insomnia.
Women who are pregnant or breastfeeding, and people with high blood pressure, should not take uva ursi. People who have Crohn's disease, digestive problems, kidney or liver disease, or ulcers should not take uva ursi.
If you are being treated with any of the following medications, you should not use uva ursi without first talking to your health care provider.
Lithium -- It's possible that taking uva ursi may cause lithium, a drug taken to treat bipolar disorder, to build up to dangerous levels in the blood.
Drugs and supplements that make urine more acidic -- These include vitamin C, cranberry juice, orange juice, and other citrus fruits and juices.
Nonsteroidal anti-inflammatory drugs (NSAIDs) and corticosteroids -- Animal studies done in Japan suggest uva ursi may increase the anti-inflammatory effects of these drugs, although it isn't known whether the herb would have that effect in people.
Iron -- If you take iron supplements, take them at least 2 hours before or 2 hours after uva ursi.
Arctostaphylos uva ursi; Bearberry; Beargrape
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