Uva ursi (Arctostaphylos uva ursi), also known as bearberry, has a history of medicinal use dating back to 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 the treatment of choice for such bladder and related infections. Through modern day scientific research in test tubes and animals, uva ursi's antimicrobial properties, which can fight infection, and diuretic effects have been demonstrated. No studies on people have been done yet, however.

Uva ursi is a trailing evergreen shrub that flourishes in alpine forests in many regions, including North America, Europe, the Iberian Peninsula, Siberia, and the Himalayas. The plant thrives in humus-rich soil. Uva ursi is a dwarfed evergreen perennial with short, creeping, red-brown branches. Pink or white bell-shaped flowers bloom in the spring. Bears are said to be fond of the shiny, bright red or pink berries, which are edible but sour tasting.

The leaves, and not the berries, are used in medicinal preparations.

Uva ursi is used to treat urinary tract infections, cystitis (bladder inflammation), and kidney stones. The hydroquinone derivative, arbutin, is the chief active compound in uva ursi. It is absorbed in the stomach and converted into a substance with antimicrobial, astringent, and disinfectant properties. During urination, as it passes out of the body, it acts on the mucus membranes of the urinary tract to soothe irritation, reduce inflammation, and fight infection.

Uva ursi is commercially available as crushed leaf or powder preparations.

Pediatric

Uva ursi is not recommended for use in children under 12 years of age.

Adult

Recommended adult doses are:

• Dried herb (available in capsules): 1.5 to 2.5 grams, three to four times per day
• Tea: Pour 1 cup boiling water over 1 heaping teaspoon of dried herb. Steep for 15 minutes. Drink up to four times per day.
• Dry extract: 100 to 210 milligrams hydroquinone derivatives (as water-free arbutin) one to four times per day
• Liquid extract (1:1, 25% alcohol): 1.5 to 2.5 mL (30 to 75 drops), three to four times per day
• Tincture (1:5): 2 to 4 mL (60 to 90 drops), three to four times per day

Uva ursi should not be taken for more than one week at a time; see Precautions section for more details.

The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, contain active substances that can trigger side effects and interact with other herbs, supplements, or medications. For these reasons, herbs should be taken with care, under the supervision of a practitioner knowledgeable in the field of botanical medicine.

Because uva ursi requires an alkaline urine for its antimicrobial properties to work, those taking uva ursi should avoid eating acidic foods like citrus, pineapple, tomato. Taking some baking soda is a good way to keep the urine alkaline. Uva ursi should only be taken for short periods (no longer than a week), and not repeated more than five times in one year.

While uva ursi is considered generally safe when taken in recommended doses and for brief periods, side effects have been reported. These include nausea and vomiting, irritability, insomnia, and an increased heart rate.

Women who are pregnant or breastfeeding should not take uva ursi. It is also not recommended for those with high blood pressure.

If you are currently being treated with any of the following medications, you should not use uva ursi without first talking to your healthcare provider.

Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) and Corticosteroids
Based upon animal studies conducted in Japan, uva ursi may increase the anti-inflammatory effects of corticosteroid medications (such as prednisolone and dexamethasone) and nonsteroidal anti-inflammatory drugs (NSAIDs; commonly used for pain and inflammation, including ibuprofen and indomethacin). Additional studies are needed to confirm whether uva ursi could increase the effects of these medications in people.

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