What is the treatment for a rash on the buttocks?

Treatment of Buttock Rash

For a buttock rash without a clear infectious or systemic cause, apply hydrocortisone 1% cream thinly to affected areas 1-2 times daily for up to 7 days, combined with alcohol-free moisturizing cream containing 5-10% urea applied twice daily to the entire body. 1, 2

Initial Assessment and Diagnostic Considerations

Before initiating treatment, consider specific etiologies that present with buttock rashes:

• Parasitic infections in travelers: If the patient has traveled to tropical regions, consider onchocerciasis (diffuse pruritic dermatitis over legs and buttocks) or larva currens from Strongyloides (itchy linear urticarial rash moving 5-10 cm/hour around trunk, upper legs, and buttocks) 3
• Irritant contact dermatitis: Most common in infants but can occur in adults with incontinence or excessive moisture 4
• Secondary infection: Look for yellow crusts, discharge, or painful lesions suggesting bacterial superinfection 3

First-Line Topical Treatment

Topical corticosteroids:

• Apply hydrocortisone 1% cream (low-potency) thinly to affected areas 1-2 times daily for up to 7 days 1, 2
• For adults with more severe inflammation, consider moderate-potency steroids like prednicarbate 0.02% cream 3
• Do not apply more than 3-4 times daily as this increases systemic absorption without improving efficacy 2
• Limit initial treatment to 7 days, with reassessment after 2 weeks if continued use is needed 1

Essential Supportive Care

Barrier restoration and moisturization:

• Apply alcohol-free moisturizing creams or ointments containing 5-10% urea to the entire body at least twice daily 1, 3
• Avoid hot water, excessive washing, and irritating soaps 1, 3
• Use gentle soap substitutes and bath oils 5

Pruritus management:

• Apply urea- or polidocanol-containing lotions to soothe itching 3
• For severe pruritus, add oral antihistamines (cetirizine, loratadine, or fexofenadine) 3
• Sedating antihistamines at bedtime may help children sleep despite itching 1

When to Escalate Treatment

If no improvement after 2 weeks or worsening symptoms:

• Escalate to moderate-potency topical corticosteroids 3
• Consider oral antibiotics if secondary infection is suspected: doxycycline 100 mg twice daily or minocycline 100 mg once daily for at least 6 weeks 3
• Obtain bacterial cultures if infection is present (painful lesions, yellow crusts, discharge) 3

For severe or refractory cases:

• Short course of systemic corticosteroids (prednisone 0.5-1 mg/kg for 7 days with weaning over 4-6 weeks) 3
• Refer to dermatology if rash persists despite appropriate therapy 1

Special Considerations

Parasitic infections requiring specific treatment:

• Cutaneous larva migrans: Ivermectin 200 μg/kg single dose or albendazole 400 mg once daily for 3 days 3
• Onchocerciasis: Doxycycline 200 mg daily for 6 weeks plus ivermectin 200 μg/kg monthly for 3 months (requires specialist input) 3
• Larva currens (Strongyloides): Ivermectin 200 μg/kg for 2 days 3

Critical Pitfalls to Avoid

• Do not use potent or very potent topical corticosteroids initially, especially in children, as this increases systemic absorption risk 1
• Do not use greasy creams for basic care as they may facilitate folliculitis 3
• Avoid topical acne medications (retinoids) as they may irritate and worsen the rash 3
• Do not manipulate or pick at the rash due to infection risk 3

Reassessment Timeline

• Reassess after 2 weeks to evaluate treatment efficacy 1, 3
• If the rash persists or worsens despite appropriate first-line therapy, refer to dermatology 1
• Consider alternative diagnoses if no response to standard treatment 6, 7