What causes sunburn?
Sunburn is painful reddening of your skin caused by the UV (ultraviolet) rays in sunlight.
You're most likely to get sunburn in the middle of the day (10 AM to 3 PM) when UV rays are strongest.
The risk of sunburn is higher in people who have light skin, blue eyes, and blonde or red hair; work outdoors; have had sunburn before.
Because tanning beds use UV light to give you a tan, you can also get a burn from staying too long in a tanning bed.
What are the symptoms of sunburn?
Symptoms may start an hour after you get burned and are usually worst in the 12 to 24 hours after you get burned. You'll have painful, red skin; blisters; fever, chills, and weakness if your burn is severe.
A few days later, the burn will itch and the outer layer of skin will flake off.
Sometimes sunburned skin gets infected.
If you had a bad sunburn when you were young, you have a higher risk of melanoma (a type of skin cancer).
How do doctors treat sunburn?
For a milder sunburn, doctors will tell you to
Take over-the-counter pain medicine.
Take a cool shower or bath.
Put a cool, wet cloth, petroleum jelly, aloe, or moisturizing lotion on your sunburn.
To treat severe sunburn, doctors may give you an antibiotic cream to put on your blisters. Don't pop your blisters and keep your sunburned skin out of the sunlight for several weeks.
How do I prevent sunburn?
The best way to prevent sunburn is to stay out of the sun. There's a higher chance of getting sunburn between 10 AM and 3 PM; at high altitudes; and when sun is reflected off snow, water, or sand.
When you have to go out in the sun, stay out no longer than 30 minutes; wear a wide-brimmed hat, sunglasses, and protective clothing; and use sunscreen.
Tips for using sunscreen:
Choose a water-resistant sunscreen with an SPF (sun protection factor) of 30 or more.
Use sunscreen that protects against both UVA and UVB rays.
Apply an ounce of sunscreen to cover your body.
Apply sunscreen 30 minutes before you go out and reapply it every 2 hours.
For small areas, consider applying a sunblock that physically blocks almost all sunlight from your skin.
Copyright © 2023 Merck & Co., Inc., Rahway, NJ, USA and its affiliates. All rights reserved.