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(Oral Mucositis)


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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Oral inflammation and ulcers, known as stomatitis, may be mild and localized or severe and widespread. They are invariably painful.

Stomatitis may involve swelling and redness of the oral mucosa or discrete, painful ulcers (single or multiple). Less commonly, whitish lesions form, and, rarely, the mouth appears normal (burning mouth syndrome) despite significant symptoms. Symptoms hinder eating, sometimes leading to dehydration and malnutrition. Secondary infection occasionally occurs, especially in immunocompromised patients. Some conditions are recurrent.

Etiology of Stomatitis

Stomatitis may be caused by local infection, systemic disease, a physical or chemical irritant, or an allergic reaction (see the table Some Causes of Stomatitis); many cases are idiopathic. Because the normal flow of saliva protects the mucosa against many insults, xerostomia predisposes the mouth to stomatitis of any cause.

The most common specific causes overall include

  • Recurrent aphthous stomatitis (RAS)—also called recurrent aphthous ulcers (RAU)

  • Viral infections, particularly herpes simplex and herpes zoster

  • Other infectious agents (Candida albicans and bacteria)

  • Trauma

  • Tobacco or irritating foods or chemicals

  • Chemotherapy and radiation therapy


Some Causes of Stomatitis



Bacterial infections


Syphilis, primary or secondary


Fungal infections


Candidal infections (most common)



Mucormycosis* (more common in diabetics)

Viral infections

Herpes simplex infection, primary (mostly in young children)

Herpes simplex infection, secondary (cold sores on the lips or palate)

Varicella zoster, primary (chickenpox)

Varicella zoster reactivation (shingles)

Others (eg, infection by coxsackievirus, cytomegalovirus, Epstein-Barr virus, or HIV; condyloma acuminata; influenza; rubeola)

Systemic disorders

Cyclic neutropenia

Erythema multiforme

Pemphigoid, pemphigus vulgaris (see Bullous Pemphigoid)

Platelet disorders

Thrombotic thrombocytopenic purpura



Antiseizure drugs*


Chemotherapy drugs



Nonsteroidal anti-inflammatory drugs (NSAIDs)*

Physical irritation

Dentures that fit poorly

Broken or jagged teeth

Habitual cheek or lip biting

Irritants and allergies

Acidic foods

Dental appliances containing nickel or palladium

Occupational exposure to dyes, acid fumes, heavy metals, or metal or mineral dusts

Tobacco (nicotinic stomatitis, particularly pipe smoker’s palate [hyperkeratotic palate with red dots at the openings of minor salivary glands])

Type IV hypersensitivity reaction (eg, to ingredients in toothpaste such as sodium lauryl sulfate, mouthwash, candy, gum, dyes, or lipstick)

Aspirin, when applied topically


Recurrent aphthous stomatitis (most commonly, minor aphthae)

Head and neck radiation

* Rare.

Evaluation of Stomatitis


History of present illness should ascertain the duration of symptoms and whether the patient ever had them previously. Presence and severity of pain should be noted. The relation of symptoms to food, drugs, oral hygiene materials (eg, toothpaste, mouth rinses), and other substances (particularly occupational exposure to chemicals, metals, fumes, or dust) is sought.

Review of systems seeks symptoms of possible causes, including chronic diarrhea and weakness (inflammatory bowel disease, celiac disease); genital lesions (Behçet disease, syphilis); eye irritation (Behçet disease); and weight loss, malaise, and fever (nonspecific chronic illness).

Past medical history should ascertain known conditions that cause oral lesions, including herpes simplex, Behçet disease, inflammatory bowel disease, and risk factors for oral lesions, including immunocompromised state (eg, cancer, diabetes, organ transplant, use of immunosuppressants, HIV infection). Whether chemotherapy or radiation therapy has ever been used to manage cancer needs to be determined. Drug history should note all recent drugs used. History of tobacco use should be noted. Social history should include sexual contact, particularly oral sex, unprotected sex, and sex with multiple partners.

Physical examination

Vital signs are reviewed for fever. The patient’s general appearance is noted for lethargy, discomfort, or other signs of significant systemic illness.

The mouth is inspected for the location and nature of any lesions.

The skin and other mucosal surfaces (including the genitals) are inspected for any lesions, rash, petechiae, or desquamation. Any bullous lesions are rubbed for the Nikolsky sign (upper layers of epidermis move laterally with slight pressure or rubbing of skin adjacent to a blister).

Red flags

The following findings are of particular concern:

  • Fever

  • Cutaneous bullae

  • Ocular inflammation

  • Immunocompromise

Interpretation of findings

Occasionally, causes are obvious in the history (eg, cytotoxic chemotherapy; significant occupational exposure to chemicals, fumes, or dust). Recurrent episodes of oral lesions occur with recurrent aphthous stomatitis (RAS), herpes simplex, and Behçet disease. History of diabetes, HIV infection or other immunocompromise, or recent antibiotic use should increase suspicion of Candida infection. Recent drug use (particularly sulfa drugs, other antibiotics, and antiseizure drugs) should increase suspicion of Stevens-Johnson syndrome.

Some causes typically have extraoral, noncutaneous findings, some of which suggest a cause. Recurrent gastrointestinal symptoms suggest inflammatory bowel disease or celiac disease. Ocular symptoms can occur with Behçet disease and SJS. Genital lesions may occur with Behçet disease and primary syphilis.

Some causes usually also have extraoral, cutaneous findings.

Cutaneous bullae suggest SJS, pemphigus vulgaris, or bullous pemphigoid. Prodrome of malaise, fever, conjunctivitis, and generalized macular target lesions suggests SJS. Pemphigus vulgaris starts with oral lesions, then progresses to flaccid cutaneous bullae. Bullous pemphigoid has tense bullae on normal-appearing skin. The Nikolsky sign is usually positive in SJS and pemphigus vulgaris.

Cutaneous vesicles are typical with chickenpox or herpes zoster (see Herpesviruses). Unilateral lesions in a band along a dermatome suggest herpes zoster. Diffuse, scattered vesicular and pustular lesions in different stages suggest chickenpox.

Kawasaki disease usually has a macular rash, desquamation of hands and feet, and conjunctivitis; it occurs in children, usually those < 5 years. Oral findings include erythema of the lips and oral mucosa.

Other cutaneous lesions may implicate erythema multiforme, hand-foot-and-mouth disease (resulting from coxsackievirus), or secondary syphilis.

Some causes have isolated oral findings, including RAS, most viral infections, acute necrotizing ulcerative gingivitis (ANUG), primary syphilis, gonorrhea, and Candida.

Location of oral lesions may help identify the cause. Interdental ulcers occur with primary herpes simplex or acute necrotizing ulcerative gingivitis. Lesions on keratinized surfaces suggest herpes simplex, RAS, or physical injury. Physical injury typically has an irregular appearance and occurs near projections of teeth, dental appliances, or where biting or an errant toothbrush can injure the mucosa. An aspirin burn next to a tooth and pizza burn on the palate are common.

Primary herpes simplex infection causes multiple vesicular lesions on the intraoral mucosa on both keratinized and nonkeratinized surfaces and always includes the gingiva. These lesions rapidly ulcerate. Clinical manifestation occurs most often in children. Subsequent reactivations (secondary herpes simplex, cold sore) usually appear starting in puberty on the lip at the vermilion border and, rarely, on the hard palate.

Acute necrotizing ulcerative gingivitis causes severe inflammation and punched-out ulcers on the dental papillae and marginal gingivae. A severe variant called noma (gangrenous stomatitis) can cause full-thickness tissue destruction (sometimes involving the lips or cheek), typically in a debilitated or malnourished patient. It begins as a gingival, buccal, or palatal (midline lethal granuloma) ulcer that becomes necrotic and spreads rapidly. Tissue sloughing may occur.

Isolated oral gonorrhea very rarely causes burning ulcers and erythema of the gingiva and tongue, as well as the more common pharyngitis. Primary syphilis chancres may appear in the mouth. Tertiary syphilis may cause oral gummas or a generalized glossitis and mucosal atrophy. A common sign of HIV becoming AIDS is hairy leukoplakia (vertical white lines on the lateral border of the tongue).

C. albicans and related species, which are normal oral flora, can overgrow in people who have taken antibiotics or corticosteroids or who are immunocompromised, such as patients with AIDS. C. albicans can cause whitish, cheesy plaques that leave erosions when wiped off. Sometimes only flat, erythematous areas appear (erosive form of Candida).


  • Bacterial and viral culture

  • Laboratory tests

  • Biopsy

Patients with acute stomatitis and no symptoms, signs, or risk factors for systemic illness probably require no testing.

If stomatitis is recurrent, viral and bacterial cultures, complete blood count, serum iron, ferritin, vitamin B12, folate, zinc, and endomysial antibody (for celiac disease) are done. Biopsy at the periphery of normal and abnormal tissue can be done for persistent lesions that do not have an obvious etiology.

Systematically eliminating foods from the diet can be useful, as can changing brands of toothpaste, chewing gum, or mouthwash.

Treatment of Stomatitis

  • Cause treated

  • Oral hygiene

  • Topical agents and rinses

  • Chemical or physical cautery

Specific disorders are treated, and any causative substances or drugs are avoided. Mouth rinses that contain ethanol can cause stomatitis and should not be used.

Meticulous oral hygiene (using a soft toothbrush and salt-water rinses) may help prevent secondary infection. A soft diet that does not include acidic or salty foods is followed.

Topical measures

Numerous topical treatments, alone or in combination, are used to ease symptoms. These treatments include

  • Anesthetics

  • Protective coatings

  • Corticosteroids

  • Physical measures (eg, cautery)

For topical anesthesia of discomfort that may interfere with eating and drinking, the following may be effective:

  • Lidocaine rinse

  • Sucralfate plus aluminum-magnesium antacid rinse

A 2-minute rinse is done with 15 mL 2% viscous lidocaine every 3 hours as needed; patient expectorates when done (no rinsing with water and no swallowing unless the pharynx is involved). A soothing coating may be prepared with sucralfate (1-g pill dissolved in 15 mL water) plus 30 mL of aluminum-magnesium liquid antacid; the patient should rinse with or without swallowing. Many institutions and pharmacies have their own variation of this formulation (magic mouthwash), which sometimes also contains an antihistamine.

If the physician is certain the inflammation is not caused by an infectious organism, the patient can

  • Rinse and expectorate after meals with dexamethasone elixir 0.5 mg/5 mL (1 tsp)

  • Apply a paste of 0.1% triamcinolone in an oral emollient

  • Wipe amlexanox over the ulcerated area with the tip of a finger

Chemical or physical cautery can ease the pain of localized lesions. Silver nitrate sticks are not as effective as low-power (2- to 3-watt), defocused, pulsed-mode carbon dioxide laser treatments, after which pain relief is immediate and lesions tend not to recur locally.

Key Points

  • Isolated stomatitis in patients with no other symptoms and signs or risk factors for systemic illness is usually caused by a viral infection or recurrent aphthous stomatitis (RAS).

  • Extraoral symptoms, rash, or both suggest more immediate need for diagnosis.

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