What is the treatment for a severe and widespread itchy rash covering most of the body?

Treatment of Severe Widespread Itchy Rash

For a severe itchy rash covering most of the body, initiate treatment with regular emollients applied at least once daily to the entire body, combined with medium-to-high potency topical corticosteroids (such as betnovate, elocon, or dermovate ointment to the body; 1-2.5% hydrocortisone or eumovate to the face), plus oral antihistamines for symptomatic relief of pruritus. 1

Immediate Management Approach

First-Line Topical Therapy

• Apply emollients liberally and frequently (at least once daily to the whole body, ideally after bathing) to restore the skin barrier and reduce transepidermal water loss 1
• For widespread involvement, use approximately 100g per 2 weeks for trunk and 100g per 2 weeks for both legs in adults 1
• Use soap substitutes (aqueous emollients) instead of regular soaps, as normal soaps are dehydrating and worsen xerotic skin 1
• Avoid alcohol-containing lotions or gels; instead use oil-in-water creams or ointments 1

Topical Corticosteroid Selection by Body Area

• Face and neck: Use mild-to-moderate potency steroids (1-2.5% hydrocortisone or eumovate ointment) 1
• Body/trunk: Use potent steroids (betnovate, elocon, or dermovate ointment) applied once or twice daily 1
• Apply topical steroids for 2-3 weeks initially, then reassess 1
• Hydrocortisone can be applied not more than 3-4 times daily for itching, inflammation, and rashes 2

Oral Antihistamines for Pruritus

• Prescribe oral antihistamines such as cetirizine, loratadine, fexofenadine, or clemastine for symptomatic itch relief 1
• Note that only sedating antihistamines provide benefit through their sedative properties, particularly useful for severe pruritus affecting sleep 1
• Non-sedating antihistamines have limited value for itch in eczematous conditions 1
• Warn patients about sedative effects on driving and operating machinery 1

When to Escalate to Systemic Corticosteroids

Indications for Oral Steroids

If the rash is severe (covering >30% body surface area) with substantial symptoms or if topical therapy fails after 2 weeks, escalate to systemic treatment 1

Oral prednisolone 0.5-1 mg/kg daily should be initiated for severe widespread rash with significant symptoms 1, 3

• For mild-to-moderate severity: Start 0.5-1 mg/kg prednisolone once daily for 3 days, then wean over 1-2 weeks 1
• For severe symptoms: Consider IV methylprednisolone 0.5-1 mg/kg, converting to oral steroids on response, with weaning over 2-4 weeks 1

Additional Symptomatic Measures

For Severe Pruritus

• Urea- or polidocanol-containing lotions can soothe pruritus when applied topically 1
• Menthol-based creams may provide additional relief for severe itching 4
• Consider bathing with emollient bath oils for both cleansing and hydrating the skin 1

Avoidance Measures

• Avoid hot showers and excessive bathing, which remove natural skin lipids 1
• Keep nails short to minimize excoriation 1
• Avoid irritant clothing such as wool next to skin; recommend cotton clothing 1
• Avoid extremes of temperature 1

When to Seek Specialist Input

Dermatology Referral Indicated If:

• No improvement after 2 weeks of appropriate topical therapy 1
• Rash worsens despite treatment 1
• Diagnostic uncertainty exists 1
• Signs of secondary infection develop (crusting, weeping, pustules) 1
• Consider skin biopsy and clinical photography for severe or atypical presentations 1

Important Caveats

Infection Surveillance

• Look for signs of bacterial superinfection: crusting, weeping, or pustulation 1
• If infection suspected, add topical or oral antibiotics (such as tetracycline for ≥2 weeks) in addition to other treatments 1
• Bacterial swabs should be taken if patients don't respond to treatment 1

Steroid Safety

• Use the least potent preparation required to control symptoms 1
• Short-term application only for potent/very potent steroids (2-3 weeks maximum) 1
• Avoid prolonged use of potent steroids on the face 1
• When symptoms improve, attempt to stop steroids for short periods 1

This structured approach prioritizes rapid symptom control while minimizing adverse effects, with clear escalation pathways if initial therapy fails.