What is the treatment for aphthous ulcers (canker sores)?

Treatment of Canker Sores (Aphthous Ulcers)

Start with topical corticosteroids as first-line therapy for canker sores, combined with topical anesthetics for pain relief, and escalate to systemic therapies only for severe or recurrent cases that fail initial treatment. 1, 2

First-Line Topical Therapy

Topical Corticosteroids (Primary Treatment)

• Apply clobetasol 0.05% gel or ointment directly to dried ulcers for localized lesions 1, 3
• For widespread or hard-to-reach ulcers, use betamethasone sodium phosphate 0.5 mg dissolved in 10 mL water as a rinse-and-spit solution 2-4 times daily 1, 3
• Alternatively, use dexamethasone mouth rinse (0.1 mg/mL) for multiple ulcers 1, 2
• For more severe localized ulcers, apply clobetasol 0.05% ointment mixed in 50% Orabase twice weekly to dried mucosa 3

Pain Management (Essential Adjunct)

• Use viscous lidocaine 2% before meals to enable eating 1, 2
• Apply benzydamine hydrochloride rinse or spray every 3 hours, particularly before eating 1, 3
• Consider amlexanox 5% oral paste (topical NSAID) for severe pain 1
• Use barrier preparations like Gelclair three times daily for mucosal protection and pain control 1, 3

Oral Hygiene and Antiseptic Measures

• Clean the mouth daily with warm saline mouthwashes to reduce bacterial colonization 1, 3
• Use 0.2% chlorhexidine digluconate mouthwash twice daily as an antiseptic rinse 1, 3
• Apply white soft paraffin ointment to lips every 2 hours if lips are affected 1

Second-Line Treatment for Refractory Cases

When to Escalate

• Escalate therapy if ulcers persist beyond 2 weeks or fail to respond to 1-2 weeks of topical treatment 1, 2

Intralesional Therapy

• Administer intralesional triamcinolone injections weekly (total dose 28 mg) for persistent localized ulcers 1, 3

Systemic Corticosteroids

• Use prednisone/prednisolone 30-60 mg (or 1 mg/kg) for 1 week, then taper over the second week for highly symptomatic or severe ulcers 1, 2, 3
• This approach is reserved for cases unresponsive to topical therapy 4, 5

Third-Line Treatment for Recurrent Aphthous Stomatitis

Definition of Recurrent Disease

• Recurrent aphthous stomatitis is defined as ≥4 episodes per year 1, 6

Systemic Immunomodulatory Therapy

• Start with colchicine as first-line systemic therapy, particularly effective if the patient also has erythema nodosum or genital ulcers 1, 2, 3
• For resistant cases, consider azathioprine, interferon-alpha, or TNF-alpha inhibitors 1, 2, 3
• Apremilast may be considered in selected refractory cases 1

Critical Pitfalls to Avoid

• Never taper corticosteroids prematurely before disease control is established 1
• Avoid sodium lauryl sulfate-containing toothpastes, as well as hard, acidic, salty foods, alcohol, and carbonated drinks 5
• Do not use chemical agents or plasters to remove tissue 2
• Biopsy any solitary ulcer lasting more than 2 weeks to rule out squamous cell carcinoma 1, 6

Diagnostic Workup for Persistent or Recurrent Cases

• Refer to a specialist for ulcers lasting more than 2 weeks or not responding to treatment 1, 2
• Perform blood tests before biopsy: full blood count, coagulation studies, fasting glucose, HIV antibody, and syphilis serology 1
• Consider evaluation for underlying systemic conditions: celiac disease, inflammatory bowel disease, nutritional deficiencies (iron, folate), immune disorders, or Behçet's disease 3, 6

Treatment Algorithm Summary

1. Start all patients on topical corticosteroids + topical anesthetics + oral hygiene measures 1, 2
2. If no improvement after 1-2 weeks, add intralesional steroids or short course of systemic corticosteroids 1, 3
3. For recurrent disease (≥4 episodes/year), initiate colchicine 1, 2
4. For refractory cases despite colchicine, escalate to azathioprine or biologic agents 1, 3
5. Always biopsy ulcers persisting beyond 2 weeks to exclude malignancy 1, 6