Metronidazole effervescent tablets tend to cause tingling and burning sensations after use, which are usually normal. If the pain persists, it is considered an allergic reaction and should be treated by promptly consulting a doctor and changing to other medications. Common reactions 1, stinging, burning: vaginal inflammation stimulation will cause damage to the vaginal wall and mucous membrane of the vaginal opening, after the use of metronidazole effervescent tablets, there may be burning, pain and other uncomfortable reactions; 2, increased discharge: women infected with bacterial vaginitis, there will be abnormal leucorrhea discharge, but the vaginal wall will not break, after the use of metronidazole effervescent tablets, there will be obvious slag-like discharge from the vaginal opening After using metronidazole effervescent tablets, there will be obvious slag-like discharge from the vaginal opening, even accompanied by vulvar itching. Before using the medication, the patient can wash the vagina with warm water and then use the medication to reduce the pain. 2. If the pain persists, you should consider that you are allergic to the raw materials of the effervescent tablets, and it is better to stop using these drugs and use other plugs or gels. If the stinging pain is short and there is no redness or swelling, you can continue to use the medication; if the pain is worse and there is also redness or swelling in the vagina, stop using the medication. After the treatment is finished, you should pay attention to regular review, and review the leucorrhoea again 3-5 days after stopping the medication to understand the efficacy.