Family Medicine & Dermatology & Gastroenterology
Stomatitis (mouth sores and ulcers)
Stomatitis is a general term for any inflammation of the oral mucosa — including the lips, gums, tongue, hard and soft palate, cheeks, and floor of the mouth — manifested by ulcers, erosions, erythema, or painful whitish lesions that interfere with eating, swallowing, speaking, and quality of life. Recurrent aphthous ulcers (recurrent aphthous stomatitis — RAS) is the most common form of stomatitis in the general population — affecting 15 to 20% of adults with unexplained recurrent episodes of painful oral ulcers with a grayish center and erythematous border — but stomatitis can also result from infections (herpes simplex virus + VZV + Candida + enteroviruses) + drug reactions + systemic diseases (Crohn’s disease + UC + lupus + Behçet’s syndrome + celiac disease + iron-deficiency or megaloblastic anemia + immunodeficiencies) + and cancer treatments (chemotherapy + head and neck radiation therapy). The clinical distinction between these different etiologies is fundamental because it entirely determines the therapeutic approach—and recurrent or severe stomatitis should always prompt investigation for an underlying systemic disease, particularly if it is accompanied by extraoral manifestations.
Classification and main causes
| Type | Agent / Cause | Characteristic presentation | Treatment |
|---|---|---|---|
| Recurrent aphthous stomatitis | Idiopathic + multifactorial (stress + local trauma + foods [nuts + cheeses + tomatoes] + hormonal fluctuations + genetic predisposition) | Rounded or oval ulcers + grayish-yellow base + erythematous halo + very painful + non-keratinized mucosa (inner surface of cheeks + lips + vestibular floor + floor of the mouth) + no fever + duration 7–14 days + healing without scarring + 3 forms: minor (<1 cm — 80 %) + major (>1 cm — 10 % — heal) + herpetiform (multiple small confluent ulcers — 10 %) | Triamcinolone acetonide in paste (Orabase®) + chlorhexidine mouthwash + viscous lidocaine PRN + colchicine 0.5 mg × 2/day for frequent relapses + thalidomide (severe forms — strict monitoring) |
| Herpetic stomatitis (HSV-1) | Herpes simplex virus Type 1 — Primary infection or reactivation | Primary infection (acute herpetic gingivostomatitis in children): high fever + cervical lymphadenopathy + multiple diffuse vesicles + erosions + keratinized AND non-keratinized mucosa + very painful + feeding difficulties + reactivation (cold sores): clustered vesicles on the lip + vermilion border | Severe primary infection: acyclovir 200–400 mg 5 times/day for 5–7 days (or valacyclovir) + start within 72 hours + analgesics + hydration + mild reactivation: topical acyclovir cream + oral valacyclovir for frequently recurring forms (prophylaxis) |
| Oral candidiasis (thrush) | Candida albicans — Immunosuppression + antibiotics + inhaled corticosteroids | Creamy whitish patches on the oral mucosa, easily removed with a spatula (leaving a bleeding erythematous mucosa), erythematous form (red, painful mucosa under a dental prosthesis), and angular form (cheilosis of the corners of the lips). | Nystatin oral suspension 100,000 IU/mL × 4/day × 7–14 days OR fluconazole 150 mg single dose (severe forms) OR 100 mg/day × 7–14 days + rinse mouth after inhaled corticosteroids |
| Hand, foot, and mouth disease | Enterovirus (Coxsackievirus A16 + A6 + Enterovirus 71) | Child < 10 years old ++ + erosive vesicles in mouth + vesicular rash on palms + soles + buttocks + moderate fever + very contagious + daycare outbreaks + duration 7–10 days | Symptomatic treatment only (acetaminophen + ibuprofen + hydration) + NO antiviral + return to daycare possible as soon as fever-free |
| Drug-induced stomatitis | Methotrexate + 5-fluorouracil + cyclosporine + NSAIDs + ACE inhibitors + sartans + beta-blockers + nicorandil + mTOR inhibitors (everolimus + sirolimus) | Aphthoid or diffuse ulcerations + often dose-related + temporal evolution linked to drug introduction + mTOR inhibitors → characteristic dose-dependent aphthous stomatitis | Dose reduction or discontinuation of the responsible medication + triamcinolone or dexamethasone mouthwash + ketamine 20 mg mouthwash (mTOR inhibitors) + spontaneous healing upon discontinuation |
| Stomatitis of systemic diseases | Crohn's disease + Ulcerative colitis + Behçet's disease + Lupus + Celiac disease + Iron deficiency anemia + Megaloblastic anemia + Neutropenia + HIV | Severe or atypical recurrent aphthae + delayed healing + or accompanied by extra-oral signs → systematic workup if unexplained recurrent stomatitis | Treatment of the causal systemic disease + local treatment of oral lesions |
Recurrent aphthous stomatitis (RAS) - detailed management
- Triggers to identify and avoid: Emotional stress + local trauma (accidental biting + aggressive brushing + hard foods + ill-fitting dentures) + specific trigger foods (nuts + almonds + fermented cheeses + tomatoes + pineapple + chocolate + spices) + menstrual cycles (peri-menstrual canker sores in some women) + sodas (sodium lauryl sulfate in some toothpastes → mucous membrane irritant → use SLS-free toothpaste)
- Local treatment of episodes: 0.1% triamcinolone acetonide % oral mucosal paste (Orabase® — Kenalog®) applied directly to the ulcer 3–4 times daily after meals → reduction in pain and duration → sucralfate oral suspension + 0.12% chlorhexidine % mouthwash 2 times daily (reduction in duration + recurrences) + viscous lidocaine 2 % PRN (local anesthesia before meals) + Orabase® cover
- Colchicine (moderate to severe recurrent gout): 0.5 mg twice daily orally continuously, reduces the frequency and severity of flares, anti-inflammatory mechanism (inhibition of neutrophil migration), adverse effects: diarrhea, nausea (dose-dependent), interaction with statins, CYP3A4
- Dapsone + pentoxifylline + thalidomide reserved for severe or refractory forms + specialists only + thalidomide → strictly teratogenic (REMS program mandatory) + peripheral neuropathy + venous thrombosis
Chemotherapy-induced stomatitis
- Mechanism: agents alkylating agents + antimetabolites (5-FU + methotrexate) → destruction of rapidly renewing oral epithelial cells → oral mucositis → extensive ulcerations + superinfection (Candida + HSV) → intense pain + inability to feed
- Grade (OMS 0–4): grade 0 = no mucositis + grade 1 = painful erythema + grade 2 = erythema + ulcers + can eat solids + grade 3 = ulcers + can only eat liquids + grade 4 = inability to eat orally → grade 3–4 = indication for parenteral or enteral nutrition
- Prevention and treatment: Oral cryotherapy (ice chips during 5-FU infusion - vasoconstriction → reduced mucosal exposure to 5-FU) + supportive mouthwash (sodium bicarbonate + chlorhexidine) + keratinocyte growth factor (palifermin - Kepivance® - in hematology) + low-level laser therapy (LLLT - photobiomodulation) → reduces mucositis severity and duration + prophylactic antifungal treatment (fluconazole) + prophylactic antiviral treatment (acyclovir if HSV seropositive) + appropriate analgesia (opioids if grade 3-4)
ℙ️
Any patient with recurrent oral aphthous ulcers (more than 3 episodes per year) and/or concurrent genital aphthous ulcers and/or uveitis should be evaluated for Behçet's disease (vasculitis of small and large vessels with recurrent oral and genital aphthous ulcers, uveitis, neurological, joint, and vascular manifestations). The classic triad of Behçet's disease (oral aphthous ulcers, genital aphthous ulcers, and uveitis) should be actively sought, as Behçet's disease is underdiagnosed in North America and can lead to serious complications if untreated.
Recommended workup for recurrent unexplained stomatitis
- Baseline biological workup NFS (neutropenia + anemia) + ferritin + B12 + folate (deficiencies → canker sores) + CRP + ESR + blood sugar + liver panel
- HIV Serology if risk factors or recurrent severe canker sores
- Anti-transglutaminase IgA + Total IgA antibodies Celiac disease (aphthous ulcers ++ with iron + B12 + folate deficiency)
- Autoimmune workup if systemic diseases are suspected: ANA + anti-dsDNA + ANCA + pathergy test (Behçet's disease—intradermal prick → pustule ≥ 48 hours = positive)
- Dental and stomatology consultation: Evaluation of prostheses + occlusal trauma + dental infectious foci
Medical consultation recommended
Consult a doctor if recurrent oral ulcers (more than 3 episodes per year), large size (> 1 cm), or not healing within 3 weeks despite local treatment, or accompanied by genital ulcers, uveitis, weight loss, diarrhea, or persistent systemic signs. A single oral lesion persisting for more than 3 weeks without spontaneous healing should prompt the elimination of oral squamous cell carcinoma through biopsy. For the evaluation of recurrent stomatitis, prescription of local and systemic treatments, and referral to dentistry or gastroenterology based on results, Clinique Omicron offers medical consultations at its locations in Quebec and through telemedicine. To book an appointment, visit cliniqueomicron.ca.
Consult at Clinique Omicron
Clinique Omicron's physicians and nurse practitioners (NPs) diagnose and differentiate between various forms of stomatitis (aphthous + herpetic + candidal + drug-induced + systemic), prescribe appropriate local treatments (triamcinolone + chlorhexidine + antifungals + antivirals), initiate systemic workup for unexplained recurrent stomatitis (CBC + ferritin + B12 + folate + anti-transglutaminase antibodies), investigate for Behçet's disease if the presentation is suggestive, and refer to dentistry + gastroenterology or hematology based on the results. Consultations are available at several service locations in Quebec and via telemedicine. To book an appointment, visit cliniqueomicron.ca.
The content of this page is provided for informational purposes only and does not substitute for professional medical or dental advice. An oral ulcer that persists for more than 3 weeks without spontaneous healing should be biopsied to rule out squamous cell carcinoma—particularly in smokers and alcohol consumers. Recurrent aphthous ulcers with genital ulcers and uveitis should suggest Behçet's disease.
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