Acute skin inflammation caused by overexposure to ultraviolet radiation from sunlight or other sources. More common and severe in light-skinned people, it ranges from mild redness and tenderness to intense pain, edema, and blistering, sometimes with shock, fever, and nausea. The process begins after 15 minutes in the sun, but redness starts 6–12 hours later and peaks within a day. Pigment cells in the skin increase melanin production (tan). Cold compresses and analgesics reduce pain. Limiting sun exposure, using sunscreen, and wearing protective clothing can prevent severe sunburn. Long-term sun exposure can eventually cause skin cancer, as well as skin wrinkling and thickening.