Uva ursi as a dietary supplement
Uva ursi, commonly known as bearberry, is a low-lying evergreen plant whose leaves are traditionally used as a dietary supplement, primarily for urinary health. It has a historical usage for treating bladder infections, with its main active component, arbutin, once widely prescribed as a urinary antiseptic before the advent of sulfa antibiotics. Recommended dosages typically range from 400 to 800 milligrams of arbutin daily, though this should not exceed two weeks of use and five times a year due to potential toxicity concerns. Uva ursi is believed to work best in alkaline urine, and caution is advised against combining it with vitamin C or cranberry juice, which can alter urine acidity.
While marketed for bladder infections, evidence supporting its efficacy remains limited, with some studies suggesting potential benefits but lacking robust clinical validation. Notably, safety issues arise from hydroquinone, a breakdown product of arbutin, which poses risks such as liver toxicity and carcinogenic effects, making long-term use inadvisable. Uva ursi is generally not recommended for young children, pregnant or nursing women, and individuals with severe liver or kidney disease. As such, those considering it should consult healthcare professionals to weigh the potential benefits against the associated risks.
Uva ursi as a dietary supplement
DEFINITION: Natural plant product used as a dietary supplement for specific health benefits.
PRINCIPAL PROPOSED USE: Bladder infection treatment
Overview
The uva ursi plant is a low-lying evergreen bush whose berries are a favorite of bears, hence the related name “bearberry.” The plant's leaves are used medicinally.
Uva ursi has a long history of being used to treat urinary conditions in both the Americas and Europe. Until the development of sulfa antibiotics, its principal active component, arbutin, was frequently prescribed as a urinary antiseptic.
Therapeutic Dosages
European recommendations indicate that the dosage of uva ursi should be adjusted to provide 400 to 800 milligrams of arbutin daily. Because of fears of toxicity, this dosage should not be exceeded; furthermore, the herb should not be used for more than two weeks and no more than five times a year.
Uva ursi should be taken with meals to minimize gastrointestinal upset. Uva ursi (based on its arbutin content) is thought to be most effective in alkaline urine, and for this reason, it should not be combined with vitamin C or cranberry juice. Some herbal experts recommend taking it with calcium citrate to alkalinize the urine.
Uva ursi is also frequently sold with other herbs traditionally thought to be helpful for bladder infections, including dandelion, cleavers, juniper berry, buchu, and parsley.
Therapeutic Uses
Uva ursi is widely marketed for the treatment of bladder infections. However, it has not been proven effective, and safety concerns exist. One study found that the combination of uva ursi with dandelion root and leaf may help prevent UTIs from occurring, but because of the dangers of liver damage, the medical community does not endorse this method. Uva ursi may function as a diuretic, and it may treat cystitis, or bladder inflammation, and kidney stones.
Scientific Evidence
Despite uva ursi’s popularity for treating bladder infections, meaningful evidence that it works is limited. Two studies evaluated the antibacterial power of the urine of people who were taking uva ursi and found activity against most major bacteria that infect the urinary tract. However, while such findings are interesting, what is really needed is a double-blind, placebo-controlled trial to discover whether using uva ursi actually helps people with established urinary tract infections. Studies of this type have only begun to emerge for uva ursi.
One study evaluated the continuous use of uva ursi for prevention of bladder infections. This double-blind, placebo-controlled trial followed fifty-seven women for one year. One-half were given a standardized dose of uva ursi (in combination with dandelion leaf, intended to promote urine flow), while the others received placebo. Over the course of the study, none of the women on uva ursi developed a bladder infection, whereas five of the untreated women did. However, this study is little more than a curiosity because most experts do not believe that continuous treatment with uva ursi is safe. An additional study looked at whether supplementation with uva ursi in women with urinary tract infections could decrease the amount of antibiotic taken without increasing symptoms. This study found beneficial results.
Safety Issues
There are significant safety concerns with uva ursi. The arbutin contained in uva ursi leaves is broken down in the intestine to another chemical, hydroquinone. This chemical is altered a bit by the liver and then sent to the kidneys for excretion. Hydroquinone then acts as an antiseptic in the bladder. However, hydroquinone is also a liver toxin, carcinogen, and irritant. For this reason, uva ursi is not recommended for long-term use. In addition, it should not be taken by young children, pregnant or nursing women, or those with severe liver or kidney disease.
Bibliography
Afshar, K., et al. "Reducing Antibiotic Use for Uncomplicated Urinary Tract Infection in General Practice by Treatment with Uva-Ursi (REGATTA) – A Double-Blind, Randomized, Controlled Comparative Effectiveness Trial." BMC Complementary and Alternative Medicine, vol. 18, no. 203, 2018, doi.org/10.1186/s12906-018-2266-x. Accessed 16 Sept. 2024.
Cybulska, P., et al. "Extracts of Canadian First Nations Medicinal Plants, Used as Natural Products, Inhibit Neisseria gonorrhoeae Isolates with Different Antibiotic Resistance Profiles." Sexually Transmitted Diseases, 2011, DOI: 10.1097/OLQ.0b013e31820cb166.
Trill, J., et al. "Uva-ursi Extract and Ibuprofen as Alternative Treatments of Adult Female Urinary Tract Infection (ATAFUTI): Study Protocol for a Randomised Controlled Trial." Trials, vol. 18, no. 421, 2017, doi.org/10.1186/s13063-017-2145-7.
"Uva Ursi." Icahn School of Medicine at Mount Sinai, www.mountsinai.org/health-library/herb/uva-ursi. Accessed 16 Sept. 2024.
"Uva Ursi Information." Mount Sinai, www.mountsinai.org/health-library/herb/uva-ursi. Accessed 16 Sept. 2024.