Compositions and methods for treatment and prevention of vaginal infections where the compositions include creatinine, such as protonated creatinine or creatinine salts, and optionally one or more weak acids, such as boric acid. The compositions may be used to treat and/or prevent a vaginal infection, such as bacterial vaginosis, to prevent recurrence of a vaginal infection, to treat and/or prevent a sexually transmitted disease (STD) or sexually transmitted infection (STI), and reduce the incidence and/or risk of a subject transmitting a STI or STD.