If there is a burning sensation in the vulva, the most common cause is inflammatory reaction due to bacterial vaginosis, which is accompanied by increased vaginal discharge, yellowish color and a strong fishy odor. In most cases, if there is no drug allergy, metronidazole suppositories can be inserted into the vagina for treatment and no sexual intercourse is allowed during the medication period. If the symptoms do not disappear after using metronidazole, you can go to the hospital for a routine leucorrhoea test to find out the pathogenic bacteria and then give the medication.