An ulcer inside the lip that lasts about 15 days and then returns can be a recurrent mouth ulcer (aphthous ulcer or canker sore), but because each ulcer persists for about 2 weeks, you should arrange an examination with a dentist or doctor soon, especially if it is the same spot each time.

Common causes or triggers include:

For now:

See a dentist/doctor promptly if the ulcer has not fully healed by 2 weeks, keeps coming back in exactly the same place, is hard or has raised edges, bleeds, grows, or you have neck lumps, weight loss, fever, difficulty swallowing, genital ulcers, eye redness, or frequent diarrhea. They may examine for tooth trauma and consider blood tests such as CBC, ferritin/iron, vitamin B12, and folate.

Recurrent aphthous ulcers are common, but new or worsening recurrent ulcers can be associated with nutritional deficiencies, as supported by a 2024 systematic review. Oral-ulcer history should distinguish a continuous non-healing lesion from separate recurrent episodes, as described in Scott-Brown's Otorhinolaryngology Head & Neck Surgery, oral ulceration section.

Photo mein clear typical ulcer (white/yellow center with red border) clearly nahi dikh raha. Lower lip ki inner lining mein prominent blood vessels aur halka irritation/redness dikh raha hai. Yeh photo se cancer ya exact disease diagnose nahi ki ja sakti.

Kyuki aap bata rahe hain ki yeh har 15 din mein repeat hota hai aur lagbhag 15 din rehta hai, aapko dentist or oral medicine specialist / ENT doctor ko 1 week ke andar dikhana chahiye. Same jagah par baar-baar ulcer ka common reason lower teeth ka sharp edge, tartar, filling, ya lip bite se continuous rubbing ho sakta hai. Doctor teeth aur mouth lining check karega.

Abhi:

Urgent dental/ENT review if the spot becomes hard, grows, bleeds, you feel a neck lump, have weight loss, or one ulcer does not heal completely within 3 weeks. Mouth ulcers usually resolve within a few weeks, but an ulcer persisting 3 weeks needs assessment, as stated by NHS mouth-ulcer guidance.