Aphthous ulcer
Exam Tips
- If a single oral ulcer lasts >=3 weeks, treat as cancer until proven otherwise and arrange urgent referral.
- Minor aphthae favor non-keratinized mucosa; recurrent herpes more often recurs on keratinized mucosa (for example hard palate/attached gingiva).
- Major aphthae are larger, deeper, slower to heal, and scar; herpetiform ulcers are numerous tiny painful lesions that can coalesce.
- Always screen for systemic clues: genital/ocular symptoms (Behcet), GI symptoms (IBD/coeliac), constitutional symptoms, recurrent infections, or anaemia signs.
- First-line drug strategy in UK practice is usually topical corticosteroid plus analgesic mouth care, with systemic prednisolone only for severe refractory episodes.
Definition
Recurrent aphthous ulceration is a chronic relapsing disorder causing painful, well-circumscribed, shallow oral mucosal ulcers (typically round or ovoid with an erythematous halo) in people who are otherwise systemically well. It usually starts in childhood or early adult life and classically affects non-keratinized mucosa, although major and herpetiform variants may involve wider oral sites.
Pathophysiology
The condition is thought to reflect immune dysregulation of the oral mucosa in genetically susceptible people, with a predominantly T-cell mediated response and increased pro-inflammatory cytokine activity (including TNF-alpha), leading to focal epithelial destruction and ulcer formation. Triggers such as minor trauma, psychological stress, hormonal fluctuation, smoking cessation, and micronutrient deficiency (iron, folate, vitamin B12, zinc, vitamin D) lower mucosal resilience and precipitate episodes. Clinically, three morphologies are recognized: minor (<1 cm, usually 2-5 mm, heals in about 7-14 days), major (often >=1 cm, deeper, slower healing, may scar), and herpetiform (multiple 1-2 mm ulcers that can coalesce and be very painful). See Figure: morphology comparison of minor, major, and herpetiform aphthae in an oral medicine atlas.
Risk Factors
- Family history/genetic predisposition (first-degree relatives commonly affected)
- Age under 40 years; onset often in childhood/adolescence
- Female sex
- Non-smoking status and recent smoking cessation
- Local mucosal trauma (sharp tooth, dentures, orthodontic appliances, cheek/tongue biting)
- Nutritional deficiency (iron, folate, vitamin B12, zinc, vitamin D)
- Psychological stress/anxiety
- Possible food triggers (for example chocolate, coffee, peanuts, gluten-containing foods)
- Possible menstrual/luteal phase association in some patients
Clinical Features
Symptoms
- Recurrent painful oral ulcers causing discomfort with eating, drinking, and speaking
- Burning or tingling prodrome before ulcer appears (some patients)
- Frequent relapses (from occasional episodes to near-continuous disease in severe cases)
Signs
- Minor aphthae: 2-4 mm round/ovoid shallow ulcers with erythematous margin, often in crops (up to about 6), mainly on non-keratinized mucosa
- Major aphthae: larger, deeper ulcers (often >=1 cm), more painful, slower healing (10-40 days), can scar
- Herpetiform aphthae: numerous pinhead ulcers (1-2 mm), may coalesce into larger erosions, often very painful
- Usually no fever or systemic toxicity in simple recurrent aphthous ulceration
- Look for local traumatic source and for red flags (single ulcer >3 weeks, induration, neck nodes)
Investigations
Management
Lifestyle Modifications
- Explain benign but recurrent natural history; many improve with age
- Avoid individual triggers (trauma, specific foods/drinks); consider SLS-free toothpaste trial
- Correct local trauma with dental review (sharp teeth, poor dentures, orthodontic irritation)
- Maintain oral hygiene and hydration; use soft toothbrush during flares
- Assess and replace nutritional deficiencies where found
Pharmacological Treatment
Topical anaesthetic/analgesic
- Benzydamine 0.15% mouthwash: 15 mL rinse/gargle every 1.5-3 hours as needed
- Lidocaine 2% oral solution (viscous): 5-10 mL swill/spit before meals, up to every 3 hours as needed
Use for symptom relief. Warn about transient stinging/numbness; avoid eating immediately after lidocaine due to bite/aspiration risk. Avoid benzydamine in known hypersensitivity.
Topical antiseptic/antimicrobial adjunct
- Chlorhexidine gluconate 0.2% mouthwash: 10 mL for 1 minute twice daily
- Doxycycline rinse (off-label): dissolve 100 mg capsule in water, hold/rinse then spit once daily for short course
Chlorhexidine may reduce secondary infection and discomfort but can stain teeth/tongue and alter taste; separate from toothpaste use. Doxycycline rinse is off-label; avoid in pregnancy and in children under 12 years.
Topical corticosteroid (first-line anti-inflammatory for recurrent/painful disease)
- Hydrocortisone buccal tablet 2.5 mg: allow 1 tablet to dissolve adjacent to lesion 4 times daily
- Betamethasone soluble tablet 500 micrograms (off-label rinse): dissolve in water and rinse/spit 2-4 times daily
- Beclometasone inhaler 50-100 micrograms per actuation (off-label): puff directly onto ulcer 2-4 times daily
Start early in prodrome/first ulcer signs. Contraindications: untreated oral infection/hypersensitivity. Safety: risk of oral candidiasis with prolonged use; advise spit out after rinses and monitor if frequent courses needed.
Systemic corticosteroid (severe, refractory episodes)
- Prednisolone oral 30 mg once daily for 5-7 days, then stop or taper according to clinical response
Reserve for severe disease after excluding infection and malignancy. Cautions: diabetes, hypertension, peptic ulcer disease, osteoporosis, mood disorder/psychosis risk, immunosuppression. Avoid repeated courses without specialist input.
Nutritional therapy
- Cyanocobalamin (vitamin B12) oral 50-150 micrograms once daily (or treat confirmed deficiency per local protocol)
Evidence suggests some benefit even when baseline B12 is normal; also replace iron/folate/other deficiencies when identified.
Complications
- Secondary bacterial infection (uncommon)
- Scarring after major aphthous ulcers
- Weight loss/dehydration risk in severe painful episodes due to reduced oral intake
- Psychological burden and reduced quality of life from frequent recurrences
Prognosis
Minor ulcers usually heal without scarring within about 1-2 weeks; major ulcers can persist for weeks and may scar; herpetiform ulcers often heal in around 10-14 days but may recur frequently. Recurrence pattern is variable (from occasional to almost continuous), but overall activity often decreases with advancing age.
Sources & References
✅NICE Guidelines(1)
- Aphthous ulcer[overview]