According to the Centers for Disease Control and Prevention, the oral antibiotic metronidazole is an effective cure for trichomoniasis, the most common curable sexually transmitted disease. Bacterial vaginosis, caused by an imbalance of vaginal bacteria, is also treated with metronidazole, according to SmarterSex.org.
Trichomoniasis is passed from an infected partner to an uninfected partner during unprotected sex, according to the CDC. Without proper treatment, the bacterial infection can last for months or, in some cases, years. Women are more likely to become infected than men, with older women being at the highest risk of infection. To prevent trichomoniasis infection, SmarterSex.org recommends using condoms during every sexual encounter.