A: This is cold sore. It is caused by a viral infection – HSV 1 (Herpes Simplex Virus 1). This type of lip ulcer is typically recurrent and severely painful. Often preceded by a blister. After the blister burst, it will reveal a raw base with crust. Without treatment, it usually heals in 2 to 4 weeks time.
This is different from the more common mouth ulcer which has a central yellow crater with surrounding red edges. Normally, there will be no blistering. This, on the other hand, is called Aphthous Ulcer.
Treatment for cold sore should be started at the first sign of symptom. If started later, it does not work as well. Severe recurrent cases will usually need oral anti-viral therapy. Anti-viral cream can be applied on the ulcer to speed up the healing process. Other symptomatic treatments are cold compress and pain-killer. Using a good lip balm also helps in symptom relief.
A word of caution: as this is a viral infection, it is highly contagious. Please avoid sharing food or kissing young children (including your partner) during this period!
By Dr. Tan
