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Urinary tract infections (UTIs) are the most common bacterial infection seen in women presenting to UK primary care, accounting for up to 3% of all GP consultations. Approximately 40-50% of women experience at least one episode during their lives. D-mannose, which is a sugar, is currently available as a food supplement. Some women find it very helpful in reducing the number of UTIs they experience, but others don’t. Previous research suggests that using D-mannose can reduce the number of UTIs experienced by women who have frequent UTIs. We aim to recruit 508 women to take the supplement or a placebo for six months. Our results should then give us the confidence to advise women who suffer with recurrent UTIs whether D-mannose might be helpful to manage their condition.

This study aims:

  • to assess the effectiveness of D-mannose in preventing symptomatic UTI,
  • to determine whether daily use of D-mannose compared with placebo by women who experience RUTIs reduces the symptom burden of UTI,
  • to determine whether daily use of D-mannose compared with placebo by women who experience RUTIs reduces antibiotic prescription for UTI.

A within trial economic evaluation will be conducted as part of this study.

Find out more:

Merit Trial - Primary Care Clinical Trials Unit