What is the best treatment approach for an adult patient with no significant medical history presenting with mouth sores?

Treatment of Mouth Sores in Adults

For an adult with no significant medical history presenting with mouth sores, begin with aggressive topical therapy using betamethasone sodium phosphate 0.5 mg in 10 mL water as a rinse-and-spit preparation four times daily, combined with benzydamine hydrochloride rinse every 3 hours before eating, while simultaneously ruling out serious systemic causes if ulcers persist beyond 2 weeks. 1, 2

Immediate Symptomatic Management

First-Line Topical Therapy

• Apply topical corticosteroids as the cornerstone of treatment: betamethasone sodium phosphate 0.5 mg in 10 mL water as a 3-minute rinse-and-spit preparation four times daily for widespread ulcers 1, 2
• For localized ulcers, use clobetasol propionate 0.05% mixed in equal amounts with Orabase, applied directly to affected areas daily 1, 2
• Use benzydamine hydrochloride rinse or spray every 3 hours, particularly before eating, to control pain 1, 2
• If pain remains inadequately controlled, add viscous lidocaine 2% (15 mL per application) as topical anesthetic before meals 1, 2

Protective and Cleansing Measures

• Apply white soft paraffin ointment to lips every 2 hours throughout the acute phase 1, 2
• Use mucoprotectant mouthwashes (e.g., Gelclair) three times daily to protect ulcerated mucosal surfaces 1, 2
• Clean the mouth daily with warm saline mouthwashes or oral sponge, sweeping gently in labial and buccal sulci to reduce risk of fibrotic scars 1, 2
• Apply antiseptic oral rinses twice daily: either 1.5% hydrogen peroxide mouthwash (10 mL) or 0.2% chlorhexidine digluconate 0.2% (10 mL) 1, 2
• Dilute chlorhexidine by up to 50% if it causes excessive soreness 1

Critical Diagnostic Workup for Persistent Cases

When to Escalate Investigation

Any mouth sore lasting more than 2 weeks, or not responding to 1-2 weeks of topical treatment, requires biopsy consideration and blood work to exclude life-threatening conditions 1, 2

Mandatory Blood Tests Before Biopsy

• Full blood count to detect leukemia, neutropenia, or anemia—widespread necrotic ulcers may indicate acute monocytic leukemia 1, 2
• Coagulation studies and fasting blood glucose to exclude biopsy contraindications 1
• Fasting blood glucose is particularly important because hyperglycemia predisposes to invasive fungal infection 1, 2
• HIV antibody and syphilis serology to rule out infectious causes 1, 2
• Consider checking 1-3-β-D-glucan and galactomannan levels if high blood glucose and fever are present, as this strongly suggests invasive fungal infection 2

Infection Screening

• Take oral and lip swabs if bacterial or candidal secondary infection is suspected 1, 2
• Treat candidal infection 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 1, 2
• Consider HSV reactivation if slow healing occurs despite appropriate treatment 1, 2

Escalation for Refractory Cases

Systemic Corticosteroids

For highly symptomatic or recurrent ulcers not responding to topical therapy, use prednisone/prednisolone 30-60 mg (or 1 mg/kg) for 1 week with tapering over the second week 2

Alternative Systemic Therapies

• Intralesional triamcinolone injections weekly (total dose 28 mg) for persistent localized ulcers 2
• Colchicine as first-line systemic therapy for recurrent aphthous stomatitis 2
• For severe refractory cases, consider azathioprine, interferon-alpha, TNF-alpha inhibitors, or apremilast 2

Critical Pitfalls to Avoid

Diagnostic Errors

• Never rely solely on topical treatments for persistent ulcers without establishing definitive diagnosis—this delays identification of malignancy, lymphoma, or life-threatening systemic disease 2, 3
• Do not delay biopsy beyond 2 weeks for persistent ulcers, as malignancy and serious systemic diseases must be excluded 3, 4
• Avoid inadequate biopsy technique (too small or superficial) that misses diagnostic features 2, 4
• If multiple sites with different morphological characteristics are present, perform multiple biopsies 1

Treatment Errors

• Do not prematurely taper corticosteroids before disease control is established 2
• Overlooking systemic causes leads to delayed diagnosis and inappropriate management 2, 3
• Stop benzocaine use if symptoms do not improve in 7 days or if irritation, pain, or redness persists or worsens 5

Specialist Referral Criteria

Refer to an oral medicine specialist for:

• Ulcers lasting more than 2 weeks 2, 4
• Ulcers not responding to 1-2 weeks of treatment 2, 4
• Recurrent, severe, or atypical presentations requiring biopsy or advanced diagnostic testing 4
• Cases with systemic symptoms (fever, weight loss) suggesting underlying disease 2
• Immediate referral if Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis is suspected based on hemorrhagic lip crusting and widespread mucosal involvement 3

Common Benign Presentations

Recurrent Aphthous Stomatitis (Most Common)

• Presents as well-demarcated, oval or round ulcers with white or yellow pseudomembrane and surrounding erythematous halo 1, 3, 4
• May be triggered by immune dysregulation, genetic predisposition, nutrient deficiency, oral trauma, anxiety, or stress 1, 4
• Topical corticosteroids are first-line treatment 6, 7

Traumatic Ulceration

• Easily diagnosed when ulcer location and shape correspond to the stimulating factor (sharp food, dental appliances, thermal burns) 1, 4
• Usually self-limiting with removal of inciting factor 8