Sunburn
Sunburn is a self-limited, acute inflammatory reaction of the skin to excessive ultraviolet radiation, mainly UVB, producing erythema, tenderness, and sometimes blistering that is confined to the epidermis. Diagnosis is clinical from the sun-exposure history and pattern of redness, and first-line treatment is UV avoidance with cool compresses, a bland moisturizer, and oral ibuprofen 200 mg every 4 to 6 hours for pain, with topical hydrocortisone 1% for itch.
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What this article covers
- Overview
Definition: sunburn is a self-limiting, acute inflammatory reaction of the skin that follows prolonged exposure to ultraviolet (UV) radiation, confined to the epidermis and behaving like a superficial (first-degree) thermal burn.
- Epidemiology
Universal exposure: sunburn is extremely common wherever people experience significant outdoor UV exposure, across all ages.
- Risk factors
Fair skin that burns easily: lower baseline melanin provides less endogenous UV protection.
- Pathophysiology
Direct DNA damage: UV radiation, chiefly UVB, is absorbed by epidermal keratinocyte DNA, generating mutations that trigger programmed cell death (the "sunburn cell").
- Clinical features
Diagnostic pattern: erythema confined to sun-exposed skin, appearing within hours of exposure and tender to touch, without prior trauma or infection, establishes the clinical picture.
- Differential diagnosis
Phototoxic drug eruption: presents as an exaggerated sunburn, often with blisters or a bluish-gray discoloration, but occurs at a UV dose that would not normally burn unprotected skin and is…
- Diagnosis
A clinical diagnosis based on exposure history and pattern establishes sunburn without laboratory testing: confluent, tender erythema limited to sun-exposed skin, arising within hours of significant…
- Management
First-line, remove the patient from ongoing UV exposure: stop further sun exposure immediately, since continued exposure worsens the epidermal injury.
- Complications
Blistering and secondary infection: broken blisters expose the underlying dermis and can become secondarily infected if not kept clean.
- Prognosis
Excellent for typical cases: uncomplicated sunburn heals spontaneously within about 1 week without residual scarring, with the outer epidermal layer peeling as it resolves.
- Prevention
Broad-spectrum sunscreen: apply sunscreen with a sun protection factor (SPF) of at least 30 about 30 minutes before sun exposure and reapply at least every 2 hours and after swimming or heavy…
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