What is the initial approach to managing pruritus?

Initial Management of Pruritus

Begin with regular emollients as the foundation of all pruritus treatment, regardless of suspected cause, and add a short course of non-sedating antihistamines if symptoms persist after 2 weeks. 1

Immediate Assessment Priorities

Determine if pruritus is localized or generalized, as this fundamentally changes your diagnostic approach—20-30% of generalized pruritus cases have significant underlying systemic disease. 1

Key History Elements

• Medication review is mandatory at initial presentation, as drug-induced pruritus is common and reversible 1
• Timing relative to water exposure (aquagenic pruritus suggests polycythemia vera) 2
• Night symptoms with constitutional signs (weight loss, fevers, night sweats) point toward lymphoma 2
• Quality and triggers of the itch help differentiate inflammatory from neuropathic causes 2, 3

Physical Examination Focus

• Examine finger webs, anogenital region, nails, and scalp systematically 4
• Distinguish primary from secondary skin lesions—primary lesions indicate diseased skin requiring dermatologic treatment, while secondary lesions (excoriations, lichenification) result from scratching 4
• Palpate for lymphadenopathy or masses, which warrant biopsy if present 2

First-Line Treatment Algorithm

Step 1: Universal Measures (All Patients)

• Prescribe emollients with high lipid content as the cornerstone of therapy, applied liberally and regularly 2, 1
• Instruct patients to keep fingernails short to minimize skin trauma from scratching 1
• Limit water exposure and avoid hot baths that worsen xerosis 1

Step 2: Pharmacologic Intervention (If Insufficient After 2 Weeks)

• Add non-sedating antihistamine: fexofenadine 180 mg daily OR loratadine 10 mg daily 1
• Avoid sedating antihistamines (like hydroxyzine) except for short-term use or palliative settings, particularly in elderly patients due to fall risk and cognitive impairment 2, 1

Step 3: Topical Therapy for Persistent Symptoms

• Apply moderate-to-high potency topical corticosteroids (mometasone furoate 0.1% or betamethasone) for localized areas 2
• Consider topical menthol 0.5% as an antipruritic agent, particularly for neuropathic components 2, 3

Initial Laboratory Workup for Generalized Pruritus

Order baseline investigations to exclude systemic causes when pruritus is generalized without obvious dermatologic explanation:

• Complete blood count with differential and ferritin (iron deficiency is common and treatable) 2, 4
• Comprehensive metabolic panel including liver function tests, creatinine, and blood urea nitrogen 2, 4
• Thyroid-stimulating hormone 4

Additional testing based on clinical suspicion:

• JAK2 V617F mutation if polycythemia vera suspected (elevated hemoglobin/hematocrit with aquagenic pruritus) 2
• Lactate dehydrogenase and ESR if lymphoma suspected 2
• HIV screening, hepatitis serologies, chest X-ray in appropriate clinical contexts 5, 4

Special Population: Elderly Patients

Treat elderly patients with emollients and topical steroids for at least 2 weeks first to exclude asteatotic eczema, which is extremely common in this age group 1

• Use moisturizers with high lipid content preferentially 2
• Never prescribe sedating antihistamines due to increased adverse effects 2, 1
• Consider gabapentin for persistent pruritus after excluding asteatotic eczema 2, 1
• Maintain high suspicion for bullous pemphigoid, which can rarely present with pruritus before blistering 1

Refractory Cases: Second-Line Options

If symptoms persist despite 2-4 weeks of appropriate first-line therapy:

• Gabapentin or pregabalin for neuropathic pruritus 2, 3
• Combination H1 and H2 antagonists (add ranitidine or famotidine to H1 blocker) 1
• Topical doxepin as alternative antipruritic 1
• SSRIs (paroxetine, sertraline) or mirtazapine for central modulation 2, 1, 3

When to Refer to Secondary Care

Refer immediately if:

• Diagnostic uncertainty after initial workup 2, 1
• Symptoms persist despite 4 weeks of appropriate primary care management 2, 1
• Suspected lymphoma or polycythemia vera based on history or laboratory findings 2
• Persistent unexplained generalized pruritus in older patients (consider occult malignancy) 2, 4

Critical Pitfalls to Avoid

• Do not assume all pruritus is benign dry skin or allergies—20-30% have significant underlying causes requiring investigation 1
• Do not prescribe sedating antihistamines routinely, especially in elderly patients 2, 1
• Do not delay investigation if pruritus is generalized and persistent beyond 6 weeks 2, 1
• Do not overlook medication history—many drugs cause pruritus as an adverse effect 1
• Do not perform exhaustive malignancy screening without clinical indicators—thorough history and physical examination guide targeted investigation 2