Initial Management of Itchy Skin Rash

Clinical Assessment and History

• The British Journal of Dermatology recommends considering the onset and duration of the itchy skin rash, with acute versus chronic (>6 weeks) being an important distinction 1
• A medication review is crucial, including any new drugs, antibiotics, or anticancer agents within the past month, as recommended by the Journal of Clinical Oncology 2
• The timing of the itch, including diurnal variation and relationship to water exposure, is an important factor to consider, according to the British Journal of Dermatology 1, 3
• A travel history is essential, as recent tropical exposure may suggest parasitic causes, as noted by the Journal of Infection 4

Physical Examination and Laboratory Workup

• The Annals of Oncology suggests that a papulopustular rash may indicate EGFR inhibitor toxicity 5
• The Journal of Infection recommends considering linear urticarial tracks, which may suggest larva currens, and a leopard skin pattern, which may indicate onchocerciasis 4
• The Journal of Clinical Oncology recommends ordering a comprehensive metabolic panel to assess renal and hepatic function 2
• The Journal of Allergy and Clinical Immunology suggests measuring thyroid-stimulating hormone levels 6
• The British Journal of Dermatology recommends iron studies to assess for iron deficiency 1

Symptomatic Management

• The Annals of Oncology recommends using topical moderate-to-high potency corticosteroids, such as mometasone furoate 0.1% or betamethasone valerate 0.1%, for mild-to-moderate pruritus (Grade 1-2) 8, 5
• The Journal of Allergy and Clinical Immunology suggests that antihistamines have limited value in atopic dermatitis and should not be used routinely 6
• The Annals of Oncology recommends using second-generation non-sedating antihistamines, such as loratadine 10 mg daily, for daytime pruritus, and first-generation sedating antihistamines, such as diphenhydramine 25-50 mg or hydroxyzine 25-50 mg at bedtime, for nighttime pruritus affecting sleep 8, 5

Condition-Specific Considerations

• The British Journal of Dermatology recommends trialing cessation of the offending agent if medication-related rash is suspected 1
• The Journal of Clinical Oncology suggests following a grading system for patients on anticancer agents, with treatment continuation for Grade 1 and hold for Grade 3 until improvement to Grade 0-1 2, 5
• The Journal of Allergy and Clinical Immunology recommends measuring total IgE and IgG-anti-TPO levels to distinguish autoallergic from autoimmune subtypes of chronic spontaneous urticaria 6

Escalation and Referral

• The Journal of Clinical Oncology recommends consulting dermatology if treatment is held due to Grade 3 severity (>30% body surface area with moderate-severe symptoms limiting self-care) 2
• The Annals of Oncology suggests using short-term oral corticosteroids, such as prednisone 0.5-1 mg/kg/day, for severe refractory pruritus (Grade 3-4) 2, 8
• The British Journal of Dermatology recommends considering phototherapy (narrowband UVB) for uremic or lymphoma-associated pruritus 1