In short. A sore or crust that does not heal, a one-sided change, numbness, or sudden deep fissuring with inflammation. Findings not to treat as an aesthetic concern.
Key points
- How long has it been there, and is it on one side?
- Something present for a few days after a knock or a cold sore is not the same as something present for two months without a reason.
- Something symmetrical and gradual is not the same as something one-sided or new.
Most perioral lines are an ordinary ageing change and can wait for a planned assessment. A small number of lip findings are different, and they must not be treated as an aesthetic concern, because doing so delays something that is treated more easily early.
A sore that does not heal
A simple injury or cold sore settles within about two weeks. A sore, ulcer or crust that is still present after three or four weeks, that is enlarging, that bleeds, or that recurs in exactly the same place is examined. The lip takes sunlight more directly than the cheek and has little pigment to protect it, which is why it is a common site for lesions that need to be looked at rather than moisturised.
A change confined to one side
Ageing and sun damage are broadly symmetrical, because they affect both sides of the mouth alike. A change on one side only, whether it is a line, a swelling, a patch or a change in the way the lip sits, has a cause that deserves a diagnosis. It is not something to be treated cosmetically until it has been explained.
Two questions that change the response
How long has it been there, and is it on one side? Something present for a few days after a knock or a cold sore is not the same as something present for two months without a reason. Something symmetrical and gradual is not the same as something one-sided or new. The second of each pair is a medical appointment before a cosmetic one.
Numbness or altered sensation
Numbness, tingling, burning or a loss of sensation in the lip or the chin is a neurological finding rather than a skin one. It is assessed promptly, and it is also a reason to postpone any injection into the area until it has been explained.
Sudden deep fissuring with inflammation
A lip that has developed deep cracks accompanied by swelling, redness and soreness over days is an inflammatory or infective problem rather than dryness. It needs a diagnosis and specific treatment. A recurring blister in the same spot is managed specifically.
A lip that has changed size or shape over weeks
Lips change over years, not weeks. A lip that has become swollen and stayed swollen, or a mouth whose shape has altered over a short period, has a cause that should be identified before anything is injected into it.
See a doctor before a cosmetic plan
- A sore, ulcer or crust that has not healed within a few weeks, or that bleeds or recurs.
- A change confined to one side of the lip, or numbness or altered sensation.
- Sudden deep fissuring with swelling, or a lip that has become and stayed swollen.
What an examination for perioral lines normally covers is described in How Perioral Lines Are Assessed. The cases where the honest answer is to treat nothing are set out in When Not to Treat Lip Lines.
Frequently asked questions
How long should a sore on the lip take to heal?
A simple injury or cold sore usually settles within two weeks. A sore, ulcer or crust that is still there after three or four weeks, that is enlarging, that bleeds, or that keeps recurring in exactly the same spot is examined rather than treated with lip balm. The lip is a common site for sun-related lesions, and they are treated far more easily when they are found early.
What does numbness in the lip or chin mean?
It means sensation is altered, which is a neurological finding rather than a skin one. It is assessed promptly, because the causes range from something minor and temporary to something that needs investigating, and none of them is addressed by treating the mouth cosmetically. It is also a reason to defer any injection into the area until it has been explained.
Can cracked corners simply be dryness?
Often yes, particularly in cold weather or with a habit of licking. Where the corners are persistently cracked, sore, red or bleeding despite ordinary lip care, that is an inflammatory or infective problem rather than dryness, and it needs a diagnosis. It also matters practically, because treating it as dryness delays something simple and treats it with the wrong thing.
Risks & Limitations
- Perioral lines have several contributors and none of the options erases them. Relaxing the muscle reduces movement, adding volume changes how the mouth folds, and resurfacing softens what is set in the skin. All of it needs maintaining.
- The lip border is a high-movement area with thin tissue and very little padding beneath it, so material placed there behaves differently from elsewhere in the face and the result depends on technique and on experience rather than on volume.
- Injectables carry risks that depend on the area treated and on the person placing them, including asymmetry, nodules and, rarely, vascular problems. Resurfacing carries downtime and a risk of pigment change that is greater in deeper skin tones.
- An active sore, an unhealed lesion, an infection or inflamed cracked corners are reasons to defer treatment, because injecting or resurfacing through them risks a problem being missed or made worse.
When to Seek Care
- A sore, ulcer or crust on the lip that has not healed within a few weeks, or that bleeds or recurs — have it examined.
- A change confined to one side of the lip, or numbness or altered sensation in the lip or chin — seek medical assessment first.
- Sudden deep fissuring with swelling and soreness, or a lip that has become swollen and stayed swollen — seek medical assessment.
- After any treatment: severe pain, blanching or mottled skin, a spreading dusky discolouration, or worsening swelling — seek urgent care.
References & Further Reading
- American Society of Plastic Surgeons (ASPS) — procedure and safety guidance
- National Institute for Health and Care Excellence (NICE, UK) — relevant guidance
- Cochrane Library — systematic reviews
- Chinese Medical Association Plastic Surgery Branch — clinical guidance
This page is patient education, not medical advice, and it does not cite individual studies. Discuss your own case with a qualified clinician. To arrange an assessment at Chongqing West District Hospital, see Contact & Consultation.