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Cancer, cold sores and allergies are causes

It’s hard to ignore a change on your lip, whether it’s your first glance in the mirror after you wake up or while you’re brushing your teeth. Your lips say a lot about your health; if you notice a bump, spot or dot on them it may be a reason to see your doctor. Or, it may be nothing to worry about.

"If you’ve got a sudden spot on or around your lips there could be a number of causes, some more serious than others," said Geisinger dermatologist Paul Long, MD.

Here’s what it could be:

Cold sore

A cold sore is an infection caused by the herpes simplex virus (HSV). These often-painful blisters are typically caused by HSV 1, but can sometimes be caused by HSV 2. About 90 percent of all people get at least one cold sore in their life; many times this happens as a child. Then, they develop antibodies and never experience a second one. Cold sores typically last seven to 10 days, during which the sore forms a blister, the blister breaks and oozes, crusts over and sloughs away.

Cold sores are most contagious when blistering and oozing; however, the virus can be transmitted even when not blistering by sharing a utensil, razor or towel, or by kissing someone. HSV 1 causes most cold sores; however, HSV2, also known as genital herpes, causes a smaller percentage of cold sores.

"Cold sores are typically nothing to worry about, unless your immune system is weakened by a disease," said Dr. Long.

Skin cancer

A discolored or dark spot on your lip may be skin cancer. Skin cancer on the lip is common but often overlooked; when people apply sunscreen to their face and body, they typically don’t consider also using a lip balm with SPF in it. Both basal and squamous cell carcinoma, the two most common types of skin cancer, could be found on the lip.

If you notice a red or dark sore or bump on your lip, you should see your doctor. 

"Since spots on your lips are highly visible, they’re more likely to be found early," said Dr. Long. "They can be treated with surgery, radiation or by freezing the cancer off."

Allergic reaction

If your lip swells suddenly, it could be an allergic reaction. Coming in contact with certain foods, pet dander, lipstick or chapstick or any other allergen could cause your lip to become inflamed and swollen. In many cases, the swelling will disappear after a short time.

However, in the case of a severe allergic reaction called anaphylaxis, you may experience other symptoms. If your mouth or face also begins to swell, you experience hives or itchy eyes and face or you have swallowing or breathing problems, get immediate medical attention.

"With anaphylaxis, your heart rate can increase while your blood pressure drops, which can cause shock and even death if you don’t get medical help immediately," said Dr. Long.

Farmer’s lip

If your lips are often dry or you have a scaly spot on your lower lip, you could have actinic cheilitis, or farmer’s lip. This patch of dry, inflamed skin resulting from long-term exposure to the sun can sometimes evolve into cancer. Your doctor will want to monitor this spot for any changes in its color or shape.

Venous lake

Older people may experience a dark spot on the lip called a venous lake, which is purple or dark blue spot commonly found on lips and ears caused by dilated blood vessels. Though they may resemble melanoma, venous lakes do not evolve into cancer, and are generally not life threatening. They are, however, unsightly. Some people opt to have them surgically removed.

Doctors don’t know why venous lakes occur, but they may be caused by sun exposure.

"If you notice a change in your lips and are unsure what’s causing it, it’s best to see your doctor," said Dr. Long. "Treating changes early, no matter the cause, gives you the best chance of effective treatment."

Geisinger dermatologist Paul Long, MD, sees patients at 1155 E. Mountain Blvd., Wilkes-Barre. To schedule an appointment with Dr. Long or another Geisinger dermatologist, please call 800-275-6401 or visit

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