What is the treatment for a canker sore (aphthous ulcer)?

Treatment for Canker Sores (Aphthous Ulcers)

Topical treatments should be the first line of therapy for canker sores, including topical steroids, pain relievers, and protective agents, followed by systemic therapies only for refractory cases. 1

First-Line Management

Topical Treatments

• Apply topical steroids as first-line therapy for accessible oral ulcers, such as clobetasol gel (0.05%) or dexamethasone mouth rinse (0.1 mg/ml) 1
• Use betamethasone sodium phosphate 0.5 mg in 10 ml water as a rinse-and-spit preparation four times daily for inflammatory conditions 1, 2
• Apply topical anesthetics like benzocaine to temporarily relieve pain associated with canker sores 3
• Consider benzydamine hydrochloride rinse or spray every 3 hours, particularly before eating, to reduce pain and inflammation 1, 2
• For severe pain, topical NSAIDs such as amlexanox 5% oral paste can be effective 1

Protective Measures

• Apply white soft paraffin ointment to lips every 2 hours to protect and moisturize 1, 2
• Use mucoprotectant mouthwashes (e.g., Gelclair) three times daily to protect ulcerated surfaces 1, 2
• Clean the mouth daily with warm saline mouthwashes to reduce bacterial load and promote healing 1, 2

Antiseptic Care

• Use antiseptic oral rinses twice daily (e.g., 1.5% hydrogen peroxide or 0.2% chlorhexidine digluconate) to reduce bacterial colonization 1, 2
• Avoid alcohol-containing mouthwashes, which can cause additional pain and irritation 2

Second-Line Management for Refractory Cases

• For ulcers that don't respond to topical therapy within 7 days, consider intralesional steroid injections (triamcinolone weekly) 1, 3
• Consider systemic corticosteroids for highly symptomatic or recurrent ulcers (prednisone/prednisolone 30-60 mg or 1 mg/kg for 1 week with tapering) 1
• For recurrent aphthous stomatitis, colchicine may be used as first-line systemic therapy 1
• In resistant cases, consider azathioprine, interferon-alpha, or TNF-alpha inhibitors 4, 1

Important Considerations

• Most canker sores are benign and self-limiting, typically healing within 7-14 days 5
• Stop treatment and consult a healthcare provider if symptoms don't improve in 7 days, or if irritation, pain, redness worsens, or if swelling, rash, or fever develops 3
• Be aware that recurrent aphthous ulcers can sometimes be a manifestation of serious health conditions such as autoimmune disorders, HIV, or hematologic conditions 5
• Carbon dioxide laser therapy has shown promise in reducing or eliminating pain and inflammation in minor aphthous ulcers 6
• Oral acyclovir has not been shown to be effective for prevention of recurrent aphthous stomatitis 7

Treatment Algorithm

1. Start with topical treatments (steroids, anesthetics, protective agents)
2. If no improvement after 7 days, consider second-line therapies
3. For frequent recurrences, evaluate for underlying systemic conditions
4. For severe cases resistant to conventional therapy, consider referral for specialized treatments like immunosuppressives or laser therapy 1, 6