A serious sunburn is like a hangover: You don't truly feel the pain until the morning after. You may get a hint of what's to come, but it takes about 12 hours to feel the full fire of overexposure. Mild (first- and second-degree) burns leave your skin hot, red, and sore and may blister, but the pain usually subsides in 24 hours. Severe third-degree burns can cause chills, headaches, and fever; the soreness often lasts for days. Here's what to do in either case.
» Apply SPF 30 sunscreen and wear a wide-brimmed hat.
» If you have sensitive skin, consider wearing pants and a long-sleeved shirt. And check your outdoors store for SPF-rated hiking clothes designed for alpine treks and people with fair skin.
» Use a lip balm that has sun protection.
» Get out of the sun during breaks, especially between 10 a.m. and 4 p.m. when ultraviolet rays are strongest.
» If you're taking any prescription drugs, check labels for warnings on sun exposure. Some antibiotics (such as tetracycline) increase the skin's vulnerability to sunburn.
» Heed the above advice with extra care when 1) traveling on snow or water, as reflected rays increase your exposure; and 2) hiking above 5,000 feet, where the strength of UV rays intensifies by 5 percent with every 1,000 feet of elevation gain.
» Apply a wet cloth (cold if possible) to the sunburned area to relieve pain and minimize swelling.
» Take a painkiller such as ibuprofen.
» Gently wash blistered skin with cool water to prevent infection.
» Keep burned areas out of the sun.
» Smear on aloe vera or a sunburn cream, but choose one without alcohol, which can sting and dry the skin.
» It's only necessary to leave the trail and see your doctor if you have blisters on your face, which can sometimes lead to scars.