Erythromycin ointment can be applied under the direction of a physician when there is a bacterial infection in the mucous membrane of the vaginal opening causing discomfort. Erythromycin is a macrolide antibiotic, which has antibacterial activity against most gram-positive bacteria, some gram-negative bacteria and chlamydia, mycoplasma. Erythromycin ointment is used for purulent skin diseases such as impetigo, small burns, infections of ulcerated surfaces and common acne. Erythromycin ointment can be applied under the direction of a physician after examination when a bacterial infection of the mucous membranes of the vaginal opening causes discomfort. Erythromycin ointment can cause irritation and allergic reactions, such as vulvar discomfort symptoms, need to go to the hospital, under the guidance of a physician reasonable use of medication, not self-medication.