The presence of redness after the use of metronidazole tablets suggests that the drug irritates the mucous membrane of the cervix, including the vagina, and may cause bleeding. In such cases, the use of metronidazole tablets should be suspended as much as possible to avoid persistent bleeding, and the vulva can be washed simply with some lotion or warm water for a few days. Bleeding after taking metronidazole tablets may also occur when the fingers touch the cervix during vaginal application, including the vaginal wall, or when the blood vessels are ruptured due to the drug being pushed too far. In such cases, it is necessary to suspend the medication as much as possible, or change to metronidazole suppositories if there is no bleeding, which will have the same therapeutic effect and greatly reduce bleeding due to the adverse effects of metronidazole effervescent tablets.