Blisters on the lips on fire should be a case of oral herpes. It is generally caused by herpes virus type I. Anti-viral treatment is mainly used, you can take oral acyclovir or ribavirin, topical antiviral ointment acyclovir ointment, generally applied 3-4 times both can improve, oral lesions can also be sprayed ribavirin spray. In addition, herpes virus is a self-limiting disease, which means that it will return to normal on its own in about a week without medication. Patients need to pay attention to rest and prevent local secondary bacterial infections, and will return to normal when the crusts fall off naturally.