Which erythema subsides in about two days?

• A. Minimal erythema
• B. Infrared radiation
• C. Ultraviolet radiation
• D. Second-degree erythema

Answer: (D)

Erythema is the skin’s reddening from increased blood flow after a stimulus, and how long it lasts depends on how strong the reaction is. The milder response, minimal erythema, appears after light exposure and fades within hours. Ultraviolet-induced erythema (sunburn) is more intense and tends to linger for several days due to ongoing inflammation and skin damage. Infrared radiation causes redness from heat and usually resolves within a day or two as the heat dissipates. Second‑degree erythema represents a more pronounced burn with greater tissue involvement, but the redness typically subsides in about two days as acute inflammation resolves, even though healing may continue afterward. That two-day timeframe is why second-degree erythema is the best match for this question.