The risks of symptomatic vaginal candidiasis after oral antibiotic therapy.

It is generally accepted that antibiotic use can result in vaginal fungal overgrowth, although evidence estimating the extent to which this causes symptomatic vaginitis is scant. In a study using the prescription of vaginal antifungal preparations as a surrogate measure of vaginal candidiasis, a cohort of women taking antibiotics had a higher incidence of vaginal candidiasis after antibiotic exposure than beforehand (relative risk 2.3; 95% confidence interval 1.9-3.0); this risk was highest in those aged 36-40 years (RR 6.0, 95% CI 2.9-12.5). The attributable risk was highest among those who were taking cephalosporins (AR 12.8%, 95% CI 9.1-16.5). In a case-control study, comparing previous antibiotic exposure among women using vaginal antifungal agents and matched controls, antibiotic exposure was higher among those using vaginal antifungal agents during the previous 28 days, with an odds ratio of 5.5 (95% CI 3.8-7.9).