How to manage pruritus triggered by cold exposure?

Pruritus Triggered by Cold: Differential Diagnosis and Management

Primary Differential: Cold Urticaria

The most important diagnosis to consider when pruritus is triggered by cold exposure is cold urticaria, a physical urticaria characterized by localized or systemic eruption of papules upon skin exposure to cold air, liquids, or objects. 1

Clinical Presentation

• Localized or widespread wheals developing within minutes of cold exposure 1
• May progress to angioedema or anaphylaxis in severe cases 1
• Symptoms can significantly impair quality of life 1

Diagnostic Approach

• Ice cube test: Apply ice cube to forearm for 5 minutes and observe for wheal formation upon rewarming 1
• Examine for primary skin lesions (wheals, papules) versus secondary lesions from scratching 2
• Visualize finger webs, anogenital region, nails, and scalp to exclude other dermatologic conditions 2

Management Algorithm for Cold-Triggered Pruritus

First-Line: Cold Avoidance and Antihistamines

• Avoidance of cold exposure is the most effective prophylactic measure 1
• Start with non-sedating second-generation H1 antihistamines: fexofenadine 180 mg daily or loratadine 10 mg daily 3, 1
• For nighttime symptoms, consider hydroxyzine 25-50 mg at bedtime 4, 3
• Caution: Avoid long-term sedating antihistamines in elderly patients due to dementia risk 5

Second-Line: Escalation for Refractory Cases

If symptoms persist after 2-4 weeks of antihistamine therapy:

• Gabapentin 900-3600 mg daily or pregabalin 25-150 mg daily 4, 3
• These agents modulate peripheral and central itch pathways 5

Adjunctive Topical Therapy

• Apply emollients liberally at least once daily to prevent xerosis 3, 6
• Use oil-in-water creams or ointments; avoid alcohol-containing lotions 3
• Menthol 0.5% preparations for symptomatic relief 4, 3
• Moderate-to-high potency topical corticosteroids (mometasone furoate 0.1% ointment or betamethasone valerate 0.1% ointment) for localized pruritus 4, 3
• Hydrocortisone 2.5% significantly decreases experimentally-induced pruritus compared to placebo 3

Alternative Differential Diagnoses

Aquagenic Pruritus

• Pruritus triggered by water exposure (which may be cold) without visible skin changes 5
• May benefit from narrowband UVB, broadband UVB, or combined UVA/UVB phototherapy 5

Xerotic Eczema (Winter Itch)

• Extremely common in elderly patients, exacerbated by cold, dry winter air 7
• Management focuses on aggressive moisturization and limiting water exposure 3, 7

Cryoglobulinemia or Cold Agglutinin Disease

• Consider if systemic symptoms (fatigue, arthralgias, purpura) accompany cold-triggered pruritus 2
• Requires laboratory evaluation including complete blood count, cryoglobulins, and cold agglutinins 2

Critical Pitfalls to Avoid

• Do not dismiss cold urticaria as trivial: Severe cases can progress to anaphylaxis with cold water immersion (swimming) 1
• Do not use topical capsaicin for cold-triggered pruritus despite its promotion for other pruritic conditions 4
• Do not use calamine lotion: No evidence supports its efficacy 4
• Do not overlook psychological impact: Cold-triggered pruritus can severely limit outdoor activities and social functioning; consider referral for psychological support in distressed patients 4

When to Escalate Care

• Refer to dermatology if symptoms are refractory to first-line antihistamines 1
• Immediate emergency evaluation if angioedema, respiratory symptoms, or signs of anaphylaxis develop 1
• Consider allergy/immunology consultation for severe or atypical cold urticaria 1