Premenstrual Syndrome:A Visual Guide to PMS Symptoms, Causes and Treatments Metrogel vaginal (metronidazole) is an antibiotic used to treat bacterial vaginosis. headache;; rash;; nausea, diarrhea; or; cold symptoms such as stuffy nose, sneezing, sore throat. . PsoriasisWhat Does a Psoriasis Rash...