Guidelines from the UK, Europe, and US recommend daily, low dose antibiotics to prevent urinary tract infections among women who experience them frequently. However, long term use of antibiotics can increase drug resistance. The study included women in the UK who had recurrent urinary tract infections (defined as two infections in six months, or three in a year). Most had experienced four or more urinary tract infections in the year before the study. Women who had underlying conditions that increase urinary tract infections (such as impaired bladder control resulting from injury or disease of the nervous system) were excluded from the study. The study concludes that methenamine could be an alternative to antibiotics for the prevention of recurrent urinary tract infections. Slightly more urinary tract infections occurred in the methenamine group, but a patient group did not consider the difference meaningful. Women’s satisfaction with treatment was similar in both groups. These results led to an ongoing review by the National Institute for Health and Care Excellence (NICE) on whether methenamine can be offered to women with recurrent urinary tract infections. The researchers say that guidelines, such as European Association of Urology Urological Infections Guidelines, could be updated to include methenamine as an option for preventing recurrent infections. This study, along with the NICE review, will allow clinicians and patients to make shared decisions and consider using methenamine rather than antibiotics. Antibiotic-resistant bacteria are particularly dangerous for some groups, such as older people. The researchers say that older women with recurrent urinary tract infections might therefore benefit more than others from methenamine. However, the study was not set up to determine which groups might benefit most from methenamine or which antibiotics were most effective.