Uva ursi (Arctostaphylos uva ursi), also known as bearberry (or beargrape), is frequently used as an astringent (which causes skin tissue to tighten), a mild diuretic (which promotes urination), and as a remedy for urinary tract infection. The plant has a long history of medicinal use as a remedy for urinary tract infections and bladder infections in the United States.
Traditionally, the astringent leaves of the Bearberry plant have been used for diarrhea and dysentery and for bladder infections and other afflictions of the urinary tract. It has also been a folk medicine in the treatment of bronchitis. Bearberry was long used as a urinary antiseptic by physicians; it was officially recognized for this purpose in the U. S. Pharmacopoeia from 1820 to 1926.
Glycoside arbutin, the main active constituent in uva ursi (bearberry) comprises up to 10 of the plant's total weight. Hydroquinone derived from glycoside arbutin and methylarbutin is a strong anti-bacterial agent and is thought to be responsible for uva ursi's beneficial effects on urinary tract infections.
Bearberry is an excellent example of an herb whose safe and effective use is far more complicated than simply preparing an herbal tea. While often described as a diuretic, uva ursi does not strongly promote urination but rather serves as a urinary antiseptic. It contains arbutin and methylarbutin which are transformed into hydroquinone in the intestine. After this compound has been absorbed by the intestine, it binds to other compounds in the urine (if the urine is alkaline), forming two additional chemicals which kill or inhibit bacteria in the urinary tract. In Germany, uva ursi is approved as a urinary antiseptic.
Bearberry is formulated in capsules, tablets, tea, and tinctures. The dried herb is generally used in preparations. In Europe, coated tablets, which dissolve in the intestinal tract instead of the stomach, are available, minimizing potential side effects. The leaves should contain at least 6 percent arbutin for reliable effects.Precautions
When taken in excessive amounts, Bearberry (Uva Ursi) may irritate and cause inflammation of the lining of the bladder and urinary tract. Supporting LiteratureMatsuda H, Nakamura S, Tanaka T, Kubo M. Pharmacological studies on leaf of Arctostaphylos uva-ursi (L) Spreng. V. Effect of water extract from Arctostaphylos uva-ursi (L) Spreng on the antiallergic and anti-inflammatory activities of dexamethasone ointment. J Pharm Soc Japan 1992;112:673-677.