What is the best course of treatment for an itchy red rash located under the breasts?

Treatment of Intertriginous Rash (Intertrigo) Under the Breasts

For an itchy red rash under the breasts, apply topical azole antifungals (clotrimazole, miconazole, or ketoconazole) to the affected area twice daily and keep the skin folds dry; if signs of bacterial superinfection develop (yellow crusting, discharge, or worsening despite antifungal treatment), add topical mupirocin or obtain bacterial cultures to guide antibiotic therapy. 1

First-Line Antifungal Treatment

The submammary area is a classic location for candidal intertrigo due to moisture, warmth, and friction in skin folds. 1

• Apply topical azole antifungals (clotrimazole, miconazole, ketoconazole, oxiconazole, or econazole) to affected areas twice daily 1
• Topical nystatin is equally effective as an alternative if azoles are unavailable or not tolerated 1
• Keep the area dry between applications—this is critical for treatment success 1

Managing Pruritus

• Apply topical low-potency corticosteroids such as hydrocortisone 2.5% or alclometasone 0.05% to reduce inflammation and itching, applied 3-4 times daily for up to 2 weeks 2, 3
• Oral antihistamines (cetirizine or loratadine 10 mg daily, or hydroxyzine 10-25 mg four times daily) can provide additional relief from itching 2
• Avoid alcohol-containing preparations in skin folds as they worsen dryness and irritation 1

Moisture Control Measures

• Use absorbent materials (clean cotton cloth or gauze) between skin folds to reduce moisture accumulation 1
• Apply alcohol-free moisturizers with urea (5-10%) to surrounding non-inflamed skin to maintain barrier function 2
• Avoid frequent washing with hot water and harsh soaps, which disrupt the skin barrier 2

When to Suspect Bacterial Superinfection

Watch for these warning signs that indicate bacterial involvement requiring different treatment 2, 1:

• Yellow crusting or discharge from the rash
• Painful skin lesions that worsen despite antifungal treatment
• Failure to respond to oral antibiotics covering gram-positive organisms after 48-72 hours
• Pustules extending beyond the intertriginous area

If bacterial superinfection is suspected:

• Obtain bacterial cultures before initiating antibiotic therapy 1
• Add topical mupirocin for suspected streptococcal infections 1
• Consider oral erythromycin for Corynebacterium infections 1
• Administer antibiotics for at least 14 days based on culture sensitivities 2

Escalation for Resistant Cases

If the rash does not improve after 7-10 days of topical antifungal therapy:

• Oral fluconazole 100 mg daily for 7-14 days can be used when topical therapy fails 1
• Reassess after 2 weeks—if no improvement, consider dermatology referral to exclude other diagnoses 2

Special Considerations

• Obese and diabetic patients are particularly susceptible to intertrigo and require more aggressive moisture control measures with regular monitoring for secondary infections 1
• If abscess formation occurs, drainage is the most important intervention to prevent progression to sepsis 1

Common Pitfalls to Avoid

• Do not use high-potency topical steroids in intertriginous areas, as they can cause skin atrophy and worsen fungal infections 2
• Do not combine topical steroids with antifungals for more than 2 weeks without reassessment, as prolonged steroid use can mask infection 2
• Do not assume all intertriginous rashes are fungal—bacterial, viral, or inflammatory conditions can present similarly and require different management 1