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

Treatment of Canker Sores (Aphthous Ulcers)

Topical treatments should be used as first-line therapy for canker sores, with benzocaine-containing products providing the most effective pain relief and topical corticosteroids accelerating healing. 1, 2

First-Line Treatments

Pain Relief

• Topical anesthetics:
  • Benzocaine-containing products (e.g., Red Cross Canker Sore Medication, Maximum Strength Anbesol, Orajel) 2, 3
  • Apply 4 times daily, particularly before eating
  • Red Cross Canker Sore Medication has shown the longest duration and greatest intensity of anesthetic effect 3
  • Viscous lidocaine 2% (15 mL per application) for more severe pain 1

Healing Promotion

• Topical corticosteroids:
  • Triamcinolone acetonide 0.1% applied 4 times daily 1, 4
  • Betamethasone sodium phosphate rinse 1
  • Clobetasol propionate for more severe cases 1

Basic Oral Care

• Warm saline mouthwashes daily 1
• Antiseptic oral rinse containing 0.2% chlorhexidine digluconate twice daily 1
• Sodium bicarbonate mouthwash (non-alcoholic, bland) 4-6 times daily 1

Second-Line Treatments

For Persistent or Severe Cases

• Mucoprotectants:

  • Sucralfate suspension for both oral and genital ulcers 5
  • Mucoprotectant mouthwash (e.g., Gelclair) three times daily 1

• Desiccating agents:

  • Single application of sulfate-based desiccating agents can reduce pain by approximately 50% by day 3 6

For Resistant Cases

• Low-Level Laser Therapy (LLLT):
  • Single application on three alternate days has shown significant reduction in pain and erythema by day 3 4
  • Complete resolution of ulcers in approximately 3 days compared to 9 days with conventional treatment 7
  • Provides immediate pain relief in most patients 8, 7

Treatment Algorithm

1. Initial presentation:

   • Start with benzocaine-containing product for immediate pain relief
   • Apply topical corticosteroid (triamcinolone acetonide 0.1%) 4 times daily
   • Implement basic oral care with saline and chlorhexidine rinses

2. After 3 days, if insufficient improvement:

   • Add mucoprotectant mouthwash
   • Consider single application of desiccating agent
   • Increase frequency of sodium bicarbonate rinse to hourly if needed

3. For persistent cases (>5 days):

   • Consider referral for Low-Level Laser Therapy
   • Evaluate for underlying factors (nutritional deficiencies, stress, allergies)

Clinical Pearls and Pitfalls

• Monitor for secondary infection: Slow healing may reflect secondary bacterial or fungal infection 1
• Frequency matters: Multiple daily applications of topical treatments are necessary for effectiveness
• Combination therapy: Using both anesthetic and anti-inflammatory agents together provides better outcomes than either alone
• Underlying factors: Consider addressing nutritional deficiencies (particularly zinc), psychological factors (stress/anxiety), and potential associations with conditions like psoriasis 1
• Avoid irritants: Acidic, spicy, or rough foods may exacerbate symptoms and delay healing

Most canker sores resolve spontaneously within 7-10 days, but appropriate treatment can significantly reduce pain and accelerate healing, improving quality of life during the episode.