Itchy Skin and Blemishes: Differential Diagnosis and Targeted Management

Common Causes & Directed Therapy

Condition	Key Features	First-Line Management
Xerosis (Dry Skin)	Fine scale, tightness, winter worsening	Ceramide-rich moisturizer BID within 3 min of bathing; humidifier 40–50%
Atopic Dermatitis (Eczema)	Flexural, chronic, personal/family atopy	TCS/TCI proactive; bleach baths; dupilumab if moderate-severe
Psoriasis	Well-demarcated silvery plaques, Auspitz sign, nail pitting	Topical vitamin D analogs + TCS; biologics for BSA >10%
Contact Dermatitis	Acute: vesicles; Chronic: lichenification; exposure history	Identify/avoid allergen (patch test); TCS short course
Acne Vulgaris	Comedones, papules, pustules, nodules; face/chest/back	Retinoid + BPO/clindamycin; isotretinoin for severe/scarring
Urticaria	Transient wheals <24 h, pruritic, blanching	2nd-gen H1 antihistamine (cetirizine 10–40 mg); omalizumab if chronic
Drug Eruption	Morbilliform, 7–14 days post-initiation	Stop culprit; TCS ± antihistamine; DRESS/SJS/TEN = emergency
Systemic (Renal, Hepatic, Thyroid, Malignancy)	Generalized pruritus without primary lesions	Treat underlying; gabapentin, naltrexone, UVB for uremic pruritus

General Skin Care Principles

• Short, lukewarm showers; non-soap cleanser (pH 5.5).
• Pat dry → moisturize immediately.
• Fragrance-free, dye-free products.
• Cotton clothing; avoid wool/synthetic against skin.

When to See Dermatology

• No improvement with 2 weeks OTC care.
• Sleep disruption, quality-of-life impact.
• Suspicious pigmented lesion (ABCDE).
• Systemic symptoms (fever, weight loss, arthralgia).