Lip lesions

What causes lip lesions?

Lip lesions have many different causes, ranging from minor everyday irritation to infections and, less commonly, cancer.

• Cold sores: Small, fluid-filled blisters caused by the herpes simplex virus (HSV-1), often starting with tingling or burning before the blister appears
• Canker sores (mouth ulcers): Small, painful ulcers that usually appear inside the mouth, including the inner lip, and are not contagious
• Minor injury or irritation: Such as biting your lip, burns from hot food or drink, or rubbing from braces or dentures
• Sun exposure: Can trigger cold sores and, over time, increase the risk of lip cancer
• A vitamin or mineral deficiency: Such as low vitamin B12, folate, zinc or iron, which can be linked to mouth ulcers
• Smoking and heavy alcohol use: Both increase the risk of lip cancer, especially when combined
• Lip cancer: A less common but serious cause of a sore, blister, ulcer or lump on the lip that will not heal.

Are there different types of lip lesions?

Lip lesions can look and behave differently depending on the cause, which can help tell them apart, though it's not always possible to be sure without seeing a doctor or dentist.

• Cold sores: Blister-like, usually on the outer lip, contagious, and typically heal within 1 to 2 weeks
• Canker sores (mouth ulcers): White, grey or yellow with a red border, usually inside the mouth, not contagious, and typically heal within 1 to 2 weeks
• Blisters: Smooth and bubble-like, filled with clear fluid or blood, often caused by biting, injury, or hot food or drink
• Persistent sores, patches or lumps: Flat or raised, may be white, red, brown or grey, don't heal within about 2 weeks, and need checking to rule out lip cancer.

How are lip lesions diagnosed?

Many lip lesions can be identified by how they look and how long they've lasted, without needing any tests. Your dentist or doctor may still want to examine you if a lesion is unusual or does not heal.

• Physical examination: Your dentist, GP or dermatologist looks at your lips, mouth, face and neck for any signs of spread
• Swab test: A sample may be taken from a sore to check for a viral infection, such as herpes simplex
• Biopsy: A small sample of tissue is removed and checked in a laboratory; this is the only way to confirm whether a lesion is cancer
• Imaging tests: Such as a CT, MRI or PET scan, used if cancer is confirmed, to check whether it has spread.

How are lip lesions treated?

Treatment depends entirely on the cause. Many lip lesions heal by themselves within a week or two with simple self-care.

• Cold sores: Antiviral cream (such as aciclovir), applied as soon as you feel tingling, or antiviral tablets for more severe or frequent outbreaks
• Canker sores (mouth ulcers): Avoiding hot, spicy or acidic food, rinsing with salt water, and over-the-counter pain relief, numbing gels or mouthwash
• Ulcers linked to a vitamin or mineral deficiency: Supplements to correct the deficiency, if one is found
• Lip cancer: Usually treated with surgery to remove the lesion, sometimes combined with radiotherapy (high-energy rays that destroy cancer cells) or chemotherapy (medicine that destroys cancer cells) for more advanced cases.

When should you see a doctor?

See a dentist or GP if:

• a sore, ulcer, patch or lump on your lip lasts longer than 2 weeks, or keeps coming back
• a sore partly heals and then comes back
• you notice bleeding, thickening, numbness or persistent pain in your lip
• you have loose teeth, or dentures that no longer fit properly
• you have a fever, difficulty swallowing, or unexplained weight loss alongside a mouth or lip sore
• you're unsure whether a lesion is a cold sore or something else.