Overview and Health Benefits
Bearberry, also known as uva-ursi (Arctostaphylos uva-ursi), is most renowned for its efficacy in treating urinary tract infections (UTIs) due to its antimicrobial, anti-inflammatory, astringent and diuretic properties. It has a long documented history of use across Europe, North America and China (Erichsen-Brown, 1979). Modern research supports many of these traditional uses, notably for the urinary system, highlighting the herb's potent bioactive compounds.
Key benefits:
- Urinary Anti-infective & Urinary Tract Health: Bearberry is effective in managing urinary tract infections (UTIs), including those affecting the bladder (cystitis) or the urethra (urethritis) (Heirich et al., 2012). The herb's primary active compound, arbutin, is metabolised into hydroquinone, which shows strong antimicrobial effects against pathogens in the urinary tract (Heinrich et al., 2012). Hydroquinone is active against many bacteria, but particularly those liable to cause UTIs, such as E. coli and Pseudomonas aeruginosa (Heinrich et al., 2012). In 1993, a preliminary report found that an extract of uva-ursi had a preventative effect on recurrent cystitis in women, concluding that it significantly reduced the number of recurrent infections compared to a placebo without causing side effects (Larsson et al., 1993). A 2018 randomised controlled trial found that a combination of plant extracts, including arbutin, effectively prevented the recurrence of UTIs by reducing bacterial load and improving urinary health (Genovese et al., 2018). Another trial the same year found that initial treatment with arbutin significantly reduced the number of antibiotic courses prescribed for women with uncomplicated urinary tract infections without increasing the symptom burden or complications (Afshar et al., 2018). Research suggests that the herb’s antiinfective activities are most effective when urine is alkaline, as acidity reduces its antibacterial properties (Bone, 2003; Mount Sinai, n.d.). Therefore, alkalinization of urine with buffering agents containing sodium bicarbonate, for example, may be desirable while using bearberry with this purpose (Bone, 2003).
- Anti-inflammatory Properties: Bearberry's anti-inflammatory effects (Lee & Kim, 2012) are particularly beneficial for the urinary system. Compounds in the herb have been shown to reduce inflammation markers (Zhang et al., 2021), providing relief from conditions like cystitis and urethritis.
- Diuretic Effects: Bearberry promotes urine production, which helps flush out toxins and pathogens from the urinary tract, aiding in the prevention and treatment of UTIs. Its diuretic action is attributed to its active compounds such as ursolic acid and arbutin, which stimulate the kidneys and increase urine production (Beaux et al., 1999).
- Antioxidant Activity: Bearberry exhibits significant antioxidant properties, helping to protect cells from oxidative damage. This activity supports overall cellular health and may reduce the risk of chronic diseases linked to oxidative stress. Studies have shown that beaberry’s phenolic acids contribute to its antioxidant capacity (Sugier et al., 2021).
- Astringent and Tonic Effects: Bearberry is known for its astringent properties, meaning its ability to tighten tissues, which helps reduce excess fluids like mucus and vaginal discharge, and soothe irritation in the urinary tract. It has also been traditionally used to strengthen bladder muscles, promoting normal contractions and easing bladder irritation (Hoffmann, 2003).
Safety
Bearberry’s high tannin content makes it unsuitable for long-term use due to potential gastrointestinal irritation and vomiting (Madaus, 1938). Bearberry is contraindicated for individuals with kidney disease and is theoretically risky for those with iron-deficient anaemia and malnutrition, as tannins can bind to metal ions and inhibit their absorption (WHO, 2004; Mills & Bone, 2013). To mitigate interaction risks, it is advised to take iron supplements at least two hours after uva-ursi (Mills & Bone, 2013). Administration of high doses of isolated hydroquinone extract has been shown to have severe effects, so taking whole plant extracts is preferable (WHO, 2004).
Pregnant and breastfeeding women should avoid uva-ursi (WHO, 2004). It is not recommended for children under 12 years old, and initial doses for children and the elderly should be smaller (Mills & Bone, 2013). Users should not be alarmed if their urine turns green, as this is a normal reaction (Heinrich et al., 2012).
As with any herbal remedy, consulting with a healthcare professional before using uva-ursi is crucial, especially for those with pre-existing medical conditions or those taking prescription medications.
