What is the treatment for itching and rash all over the body?

Treatment for Generalized Itching and Rash in a 21-Year-Old

Start with emollients applied at least once daily to the entire body and topical hydrocortisone 1-2.5% cream applied to affected areas 3-4 times daily for up to 7 days, combined with identification and removal of any triggering factors. 1, 2

Immediate First-Line Management

Topical Therapy Foundation

• Apply emollients liberally at least once daily to prevent xerosis (dry skin), which commonly triggers pruritus—use oil-in-water creams or ointments, avoiding alcohol-containing lotions 1
• Hydrocortisone 1-2.5% cream should be applied to affected areas not more than 3-4 times daily for symptomatic relief of itching associated with minor skin irritations, inflammation, and rashes 2
• Limit hydrocortisone use to 7 days maximum to avoid skin thinning and mucosal injury 3, 1
• For more persistent inflammation, consider moderate-to-high potency topical steroids (mometasone furoate 0.1% ointment or betamethasone valerate 0.1% ointment) 1

Adjunctive Topical Options

• Menthol 0.5% preparations provide symptomatic relief through counter-irritant effects 3, 1
• Clobetasone butyrate may benefit patients with generalized pruritus 4, 1
• Avoid crotamiton cream, topical capsaicin, and calamine lotion as they are not effective 4

Trigger Identification and Avoidance

Critical Environmental Factors

• Avoid soaps and detergents that remove natural lipid from skin surface—use dispersible cream as a soap substitute 4
• Eliminate exposure to irritants including woolen clothing worn next to skin; recommend cotton clothing instead 4
• Avoid extremes of temperature and keep nails short to minimize trauma from scratching 4
• Consider drug-induced pruritus—trial cessation of medications if risk-benefit analysis is acceptable 4

Bathing Recommendations

• Bathing is useful for cleansing and hydrating skin—allow patient to decide on most suitable bath oil and bathing regimen 4
• Apply emollients immediately after bathing when most effective, as they provide surface lipid film that retards evaporative water loss 4

Systemic Therapy Escalation

Second-Line: Oral Antihistamines

• Non-sedating antihistamines are preferred for daytime use: fexofenadine 180 mg daily or loratadine 10 mg daily 4, 3, 1
• Mildly sedative cetirizine 10 mg can be used as alternative 4, 1
• Sedating antihistamines (hydroxyzine 25-50 mg or diphenhydramine 25-50 mg) should only be used short-term for nighttime relief or in palliative settings, as long-term use increases dementia risk 4, 3, 1
• Combination H1 and H2 antagonists (e.g., fexofenadine plus cimetidine) may be considered 4

Third-Line: Neuropathic and Psychiatric Agents

If antihistamines fail after adequate trial:

• Gabapentin 900-3600 mg daily or pregabalin 25-150 mg daily for neuropathic component 4, 3, 1
• Antidepressants: paroxetine, fluvoxamine, or mirtazapine 4, 1
• Antiemetics: ondansetron or aprepitant 4
• Opioid antagonists: naltrexone or butorphanol 4

Essential Diagnostic Workup

Initial Laboratory Investigations

Since this is a 21-year-old with generalized pruritus and rash, baseline investigations should include 4:

• Ferritin and full blood count (to exclude iron deficiency, polycythemia vera, lymphoma)
• Urea and electrolytes (to exclude uremia)
• Liver function tests (to exclude cholestasis)
• Erythrocyte sedimentation rate if available locally
• Chest X-ray if constitutional symptoms present

Additional Testing Based on Clinical Features

• Travel history and infectious screening: Consider HIV and hepatitis A, B, C serology; screening for malaria, strongyloidiasis, schistosomiasis if travel history suggests 4
• Thyroid function tests, fasting glucose, and glycated hemoglobin only if additional clinical features suggest endocrinopathy or diabetes 4
• Skin biopsy may be necessary if persistent unexplained pruritus, as patients rarely present with normal-looking skin who prove to have skin lymphoma 4

Critical Pitfalls to Avoid

Common Treatment Errors

• Do not use sedative antihistamines long-term except in palliative care, as they predispose to dementia 4
• Do not prescribe cetirizine for uremic pruritus as it is not effective in this specific context 4
• Avoid prolonged topical steroid use beyond 7 days without reassessment, as this causes skin atrophy 3, 1
• Do not assume all pruritus is benign—in a young patient with generalized symptoms, exclude systemic causes including lymphoma, especially if accompanied by weight loss, fevers, night sweats, or enlarged lymph nodes 4, 5

When to Refer to Specialist

• Refer to secondary care if diagnostic doubt exists or if primary care management does not relieve symptoms 4
• Reassess patients who have not responded to initial treatment within 2 weeks 4
• For elderly patients with pruritus, initially treat with emollients and topical steroids for at least 2 weeks to exclude asteatotic eczema before escalating therapy 4

Alternative and Adjunctive Therapies

Phototherapy Options

• BB-UVB or NB-UVB phototherapy can be considered for refractory cases, particularly if lymphoma-associated or uremic pruritus is suspected 4, 1

Complementary Approaches

• Acupuncture in combination with Chinese herbal remedies may be considered as second-line therapy 4
• Behavioral interventions, relaxation techniques, and cognitive restructuring for psychological contributors 1