What is the treatment for a lip fissure in the corner of the mouth?

Treatment of Angular Cheilitis (Lip Fissures in the Corner of the Mouth)

Apply white soft paraffin ointment (petroleum jelly) to the lip corners every 2 hours during the acute phase, combined with a topical antifungal-corticosteroid combination cream (1% isoconazole nitrate with 0.1% diflucortolone valerate) twice daily for 7-14 days. 1, 2, 3

Immediate First-Line Treatment

Barrier Protection and Lubrication

• Apply white soft paraffin ointment to the affected corners every 2 hours throughout the day 1, 2
• This creates a protective barrier, prevents further cracking, and promotes healing 2
• Continue frequent application until fissures heal completely 1

Topical Antimicrobial-Corticosteroid Therapy

• Use 1% isoconazole nitrate with 0.1% diflucortolone valerate ointment twice daily 3
• This combination addresses the mixed bacterial-fungal etiology that characterizes most angular cheilitis cases 4, 3
• Limit corticosteroid use to maximum 7 days to avoid perianal skin thinning and atrophy 5
• If this specific combination is unavailable, alternative antifungal creams (miconazole, clotrimazole) can be substituted 3

Pain Control

• Apply topical lidocaine 5% to fissures before eating or when pain is severe 1, 2
• Use oral analgesics (acetaminophen or ibuprofen) for breakthrough pain 2
• Avoid irritating foods: spicy foods, citrus fruits, hot drinks, alcohol 2

Adjunctive Measures

Oral Hygiene and Moisture Management

• Clean the mouth daily with warm saline rinses 1
• Maintain adequate hydration by drinking sufficient fluids throughout the day 2
• Use alcohol-free mouthwash to prevent further irritation 2

Lifestyle Modifications

• Avoid smoking, which delays healing 2
• For denture wearers: ensure proper fit and cleanliness of dental prostheses 2
• Apply lip balm or petrolatum regularly, but avoid long-term continuous use due to potential mucosal dehydration 2

Critical Pitfalls to Avoid

• Never use topical corticosteroids beyond 7 days due to risk of skin atrophy and increased susceptibility to secondary infection 5
• Do not ignore persistent or recurrent fissures—these require evaluation for underlying conditions 2, 6
• Avoid manual manipulation or picking at the fissures, which worsens trauma 1

When to Investigate Further

If fissures persist beyond 2-3 weeks despite appropriate treatment, evaluate for: 2, 6, 4

• Nutritional deficiencies: Iron deficiency anemia, vitamin B12 deficiency, folate deficiency 6
• Candida infection: Obtain swab culture if fungal infection suspected 7, 3
• Bacterial infection: Consider Staphylococcus aureus, especially in immunocompromised patients 8
• Systemic conditions: Diabetes, HIV, immunosuppression, Down syndrome 6, 7
• Dermatologic diseases: Lichen planus, pemphigus, contact dermatitis 1, 6

Expected Timeline

• Pain relief typically occurs within 3-5 days of starting treatment 3
• Complete healing usually achieved within 10-14 days with appropriate therapy 3
• If no improvement after 14 days, reassess diagnosis and consider alternative etiologies 2, 6