What are the treatment options for mouth sores?

Treatment of Mouth Sores

Start with high-potency topical corticosteroids as first-line therapy: betamethasone sodium phosphate 0.5 mg dissolved in 10 mL water as a 2-3 minute rinse-and-spit solution four times daily, or clobetasol 0.05% ointment mixed in 50% Orabase applied twice weekly to localized lesions on dried mucosa. 1, 2

First-Line Topical Corticosteroid Options

The British Journal of Dermatology provides three evidence-based corticosteroid regimens for mouth sores 3, 1:

• Betamethasone sodium phosphate 0.5 mg in 10 mL water: Use as a 2-3 minute rinse-and-spit solution 1-4 times daily 3, 1, 2
• Fluticasone propionate nasules: Dilute in 10 mL water and use twice daily 3, 1, 2
• Clobetasol 0.05% ointment: Mix in equal amounts with Orabase and apply directly to localized lesions on dried mucosa twice weekly 3, 1, 2

For highly symptomatic ulcers, the Annals of Oncology recommends starting with high-potency topical corticosteroids first, specifically dexamethasone mouth rinse (0.1 mg/ml) when multiple locations are involved, or clobetasol gel/ointment (0.05%) for limited, easily accessible ulcers 3, 1.

Pain Management Strategy

Pain control should follow a stepwise approach 3:

• Mild pain: Apply mucoprotectant mouthwash (e.g., Gelclair) three times daily to protect ulcerated surfaces 3, 1, 2
• Moderate pain: Use benzydamine hydrochloride oral rinse every 3 hours, particularly before eating 3, 2
• Severe pain: Apply viscous lidocaine 2% (15 mL per application) up to 3-4 times daily 3, 2
• Refractory severe pain: Consider cocaine mouthwashes 2-5% three times daily for severe oral discomfort 3

The WHO pain management ladder should guide escalation for more severe pain, including consideration of topical NSAIDs (amlexanox 5% oral paste) or systemic analgesics 3.

Basic Oral Hygiene Measures

Implement these supportive measures alongside pharmacologic treatment 3, 2:

• Lip care: Apply white soft paraffin ointment immediately and then every 2 hours throughout acute illness 3
• Oral cleansing: Clean mouth daily with warm saline mouthwashes or oral sponge, gently sweeping in labial and buccal sulci to reduce fibrotic scar risk 3, 2
• Antiseptic rinses: Use 0.2% chlorhexidine digluconate mouthwash (10 mL twice daily) or 1.5% hydrogen peroxide mouthwash to reduce bacterial colonization 3, 2
• Dilution strategy: Dilute chlorhexidine by up to 50% if it causes excessive soreness 3
• Dietary modifications: Avoid crunchy, spicy, acidic foods and hot beverages during healing 2

For prevention in cancer patients receiving targeted therapy, the Annals of Oncology recommends sodium bicarbonate-containing mouthwash 4-6 times daily, increasing to hourly if stomatitis develops 3.

Treatment of Secondary Infections

Critical pitfall: Always screen for and treat secondary infections, as they significantly delay healing 3, 2:

• Candidal infection: Treat with nystatin oral suspension 100,000 units four times daily for 1 week, or miconazole oral gel 5-10 mL held in mouth after food four times daily for 1 week 3, 1, 2
• Herpes simplex reactivation: Consider if ulcers heal slowly despite appropriate treatment 3
• Monitoring: Take regular oral and lip swabs if bacterial or candidal infection is suspected 3

Note that hyperglycemia is an important predisposing factor for invasive fungal infections presenting as oral ulcers 2.

Second-Line Treatments for Refractory Ulcers

When topical corticosteroids fail after 2-4 weeks, escalate to 3, 1, 2:

• Tacrolimus 0.1% ointment: Apply twice daily for 4 weeks for recalcitrant lesions 3, 1, 2
• Intralesional steroids: Weekly triamcinolone injections (total dose 28 mg) in conjunction with topical clobetasol 0.05% gel/ointment 3, 1, 2

The British Journal of Dermatology found no significant difference between triamcinolone acetonide 0.1% paste and tacrolimus 0.1% ointment in a split-mouth trial, though both reduced mucosal involvement and pain scores 3.

Systemic Therapy for Severe or Recurrent Cases

Reserve systemic corticosteroids for highly symptomatic, recurrent, or esophageal lesions 3, 1, 2:

• Dosing: High-dose pulse 30-60 mg or 1 mg/kg oral prednisone/prednisolone for 1 week, followed by dose tapering over the second week 3, 1, 2
• Indication: Use when topical therapy has failed and quality of life is significantly impacted 2

For severe recurrent aphthous ulcers, a German review supports colchicine, pentoxifylline, or prednisolone as systemic options, though efficacy is debated 4. Other immunosuppressive agents should only be used for refractory cases or Behçet disease 4.

When to Investigate Further

Obtain blood work and consider biopsy if 2:

• Ulcers persist beyond 3 weeks despite appropriate treatment
• Multiple sites with different morphological characteristics are present
• Patient has systemic symptoms (fever, weight loss, malaise)

Essential investigations 2:

• Full blood count to rule out hematologic disorders (leukemia, anemia)
• Fasting blood glucose to identify diabetes as predisposing factor
• HIV antibody and syphilis serology if risk factors present

Critical Pitfalls to Avoid

• Don't assume all mouth sores are benign: Oral ulcers may be the first manifestation of Crohn's disease, Behçet disease, or hematologic malignancies 2
• Don't use acyclovir for aphthous ulcers: Oral acyclovir is not effective for prevention of recurrent aphthous stomatitis 5
• Don't overlook denture-related causes: Improperly fitting dentures can cause ulcers, stomatitis, hyperplasia, and chronic candidiasis; malignant changes can develop 6
• Don't forget sodium lauryl sulfate: Toothpastes containing this ingredient should be avoided 4
• Don't delay infection treatment: Secondary candidal or HSV infection significantly delays healing and must be treated promptly 3, 2