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Lip Sores and Inflammation


Bernard J. Hennessy

, DDS, Texas A&M University, College of Dentistry

Last full review/revision May 2020| Content last modified May 2020
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Lip inflammation may be generalized, or localized to one or more sores or lesions. Although some swelling may be present, the main manifestation is discomfort. Lip swelling with little or no discomfort is discussed elsewhere.

Lip sores and growths

A number of infectious, malignant, or premalignant disorders can cause lip sores and growths:

  • Actinic keratosis: Irregular pale, red, or variably colored dry and scaly precancerous growths. This common premalignant condition is caused by chronic exposure to ultraviolet light. Treatments include reducing sun exposure (sunscreens and hats with wide brims) and laser ablation.

  • Erythema multiforme: Multiple bullae that rupture quickly and leave crusting hemorrhagic ulcers on labial mucosa. This ulcerative mucocutaneous condition is an immune reaction usually triggered by herpes simplex virus. Erythema multiforme has a variety of appearances and often causes painful oral mucositis. Lip ulcerations are managed with topical corticosteroids or systemic steroids.

  • Primary syphilis (chancre): A painless ulcer with hard edges. Oral chancres are commonly seen on lips (upper lip more common in males; lower lip more common in females). Treatment of choice for syphilis is penicillin.

  • Herpes labialis (recurrent herpes simplex virus infection): A small cluster of fluid-filled vesicles that rupture to form an ulcer on the lip's vermilion border; commonly referred to as a cold sore or a fever blister. Treatment is most useful if started during the prodromal phase. Oral treatment includes one-day dosing of famciclovir or valacyclovir or 5 days of acyclovir. Topical acyclovir, penciclovir cream, or over-the-counter 10% docosanol cream applied multiple times per day may shorten the duration of symptoms by only 1 day or less.

  • Erythroplakia or leukoplakia: Red or white patches. These patches may be associated with dysplasia and squamous cell carcinoma.

  • Oral squamous cell carcinoma: May present variably as a hyperkeratotic nodule or plaque, ulcer with hard edges, or as erythroplakia or leukoplakia (particularly early cases that have not ulcerated). Treatment depends on clinical staging at diagnosis and includes wide surgical excision, radiation therapy, or both.

  • Verruca vulgaris (common wart): Pebbly surfaced, painless growth. This benign condition can spread by autoinoculation. Treatments include use of topical agents (salicylic acid, lactic acid, liquid nitrogen) or surgical excision.

Cheilitis (lip inflammation)

Cheilitis is acute or chronic inflammation of the lips. It may be caused by infection, sun damage, drugs or irritants, allergy, or underlying disease. Inflammation primarily affects the vermilion and vermilion border. Swelling, redness, and pain of the lips occurs; other changes may include cracks, fissures, erosions, crusts, and scale.

Angular cheilitis (angular stomatitis) is the most common form; inflammation, crusting, painful fissures, and often maceration develop in the corners of the mouth. Typical causes include

  • Excessively worn teeth or dentures that do not adequately separate the jaws, creating skin folds at the corners of the mouth in which saliva accumulates

  • Candida species (or sometimes Staphylococcus aureus)

  • Iron deficiency, vitamin B complex deficiency (especially riboflavin, cobalamin)

Treatment of angular cheilitis may involve replacing dentures or restoring proper tooth size with partial dentures, crowns, or implants, which helps reduce the folds at the corners of the mouth, and using antifungals (eg, clotrimazole cream), antibiotics (eg, mupirocin ointment), or iron or vitamin B supplementation as needed.

Other causes of cheilitis include

  • Actinic atrophy: Sun damage causing thin, atrophic mucosa with erosions; predisposes to malignancy

  • Eczematous cheilitis: Red, dry lips (sometimes termed chapped lips) typically caused by contact irritants or sometimes by allergens or as part of atopic dermatitis

Rare types of cheilitis include cheilitis glandularis, cheilitis granulomatosa, and plasma cell cheilitis. Children with Kawasaki disease may develop erythematous, dry, swollen, and cracked lips, along with strawberry tongue.

Diagnosis is usually based on history and inspection. Actinic cheilitis with signs of progression (induration, ulceration, thickening) should be biopsied to rule out carcinoma.

Treatment includes petrolatum or other emollients, as well as elimination or treatment of specific causes. For severe nonmalignant actinic cheilitis, vermilionectomy (lip shave) or CO2 laser ablation may be considered. Sun damage to the lips can be minimized through the use of protective coverings such as a wide-brimmed hat and lip balm containing topical sunscreen.

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