What does this mean?
The lip is the crossing point between the inside of the mouth and the skin of the face, and it is exposed all the time. That is why it carries the marks of the sun, of the cold and of repeated irritation more than anywhere else. What is expected of a sore here is that it scabs over, gets smaller and closes completely within two weeks.
A cold sore follows a set pattern: tingling first, then small blisters, then a scab, and healing within about a week to ten days. A sore that needs attention does not follow that pattern. The scab falls off, the surface underneath does not close and the scab forms again; its borders harden and it stays stubbornly in the same place. Time is the most useful measure here.
Widespread dryness and flaking on the lower lip, with the border between lip and skin becoming blurred, points to a separate picture. This change develops over years through the effect of the sun, and a single scab can settle on that background; it is seen more often in people who work outdoors and who spend a lot of time at the sea and in the sun. A sore that appears on such a background and does not heal may need assessing with a sample of tissue.
The cause of a sore on the lip that will not heal can range from a surface infection to sun damage built up over years; how many weeks the sore has been there, whether it keeps coming back in the same place and the general look of the lip guide the distinction.
Likely causes
What helps at home?
- Note the day the sore started and photograph it once a week in the same light; small changes are hard to follow by eye.
- Do not pick the scab off, and do not bite or lick your lip; constant irritation delays healing.
- Use a lip balm with sun protection and stay in the shade in the middle of the day; the lip is the area most often missed when sun protection is put on.
- Stop or cut down on smoking; the lip is one of the areas directly affected by smoke.
- If the sore has passed two weeks and still has not closed
- If the scab forms again in the same place every time it falls off
- If the edge of the sore has hardened, or has raised and thickened
- If the sore bleeds easily, or starts bleeding on its own
- If you can feel a hard gland under the jaw or in the neck on the same side
Frequently asked questions
- Is it a cold sore or something else, how do I tell?
- A cold sore usually comes back in the same area, starts with tingling and closes within a week to ten days without leaving a mark. A sore that appears without tingling, goes through no blister stage and passes two weeks does not fit that description. The definite distinction is made at an examination, but you can keep track of the time measure yourself.
- The sore does not hurt, should I still have it looked at?
- Yes. Some of the changes on the lip that need attention are painless, and that is exactly why they are noticed late. The absence of pain does not count as a reason to wait. Every sore that passes two weeks and does not ease should be assessed, even if it causes no pain.
- My lip is constantly dry and flaky, does that come under the same heading?
- Widespread dryness and flaking is different from a single sore, but it is not counted as unimportant. A change that has gone on for years, especially on the lower lip, blurring the border between lip and skin, suggests sun damage; it needs regular review. If there is a hardened spot or a scab that will not heal on that background, an examination should not be delayed.
This content is for general information and does not replace an in-person examination. Symptoms overlap between conditions, and a diagnosis can only be made clinically.