Hello there ,
Thanks for writing your query,
Sore spot seen on the inner surface of the upper lip
can be a apthous ulcer .
apthous ulcers are painful and may caused due recurrent trauma to the lip mucosa or
It may be caused due to several reasons like deficiency or certain vitamins especially vitamin B12
and vitamin C.
start with multivitamin
supplements for 7 to 10 days and vitamin C lozenges will help in resolving the problem.
avoid alcohol , carbonated drinks , tobacco chewing
and smoking as these may worsen the area affected.
Apply oral antiseptic ,analgesic
ointments like dentogel or mucogel topically over the affected area
The ulcer will subside slowly and gradually in 2 to 3 weeks.
i hope this helps ,