Only a few types of vulvitis might be effectively treated with erythromycin ointment application, as the treatment depends on the specific pathogen involved in the vulvitis, and not all inflammations use the same medication. First, a vaginal discharge test must be conducted, as some cases are due to yeast infections, and some are due to trichomoniasis, for which erythromycin ointment is ineffective. For instance, treatment for trichomoniasis requires both partners to simultaneously undergo treatment with oral metronidazole, otherwise, even if only the woman is treated, there is a high chance of recurrence. (Please use medications under the guidance of a doctor.)