If your mouth is on fire and blistered, you can apply vitamin B and vitamin C tablets, grind them into a powdered state, add a little water to make a paste and apply it to the mouth where it is on fire and blistered. This can replenish the oral cavity with some vitamin B and vitamin C, which can speed up the repair of the oral mucosa, and also provide some nutrition to the oral cavity, which can make the mouth fire and blisters heal sooner. In addition, the mouth blisters caused by fire, you can also apply acyclovir ointment on the affected area, and then apply some iodophor and erythromycin ointment or gentamycin ointment, etc., to disinfect and anti-inflammatory treatment. At the same time, it is best to take oral Niuhuang detoxification tablets, as well as some anti-virus oral solution, with the treatment effect will be better.