What Is Snow Blindness?

Medically Reviewed by Whitney Seltman, OD on July 10, 2023
Written by WebMD Editorial Contributors
3 min read

Snow blindness, or photokeratitis, is temporary eye pain and discomfort after exposure to too much ultraviolet (UV) light. It’s like a sunburn on your eyes. It’s usually not serious and will heal on its own within a few days.  

‌Direct sunlight gives off invisible UV rays of energy that reach the Earth. UV rays cause sunburns when you’re not using sunscreen, shade, or clothing to protect your skin.

Snow blindness happens when UV rays damage your eyes. The surfaces of your eyes are sensitive to UV rays, just like your skin. This sensitivity makes you squint in bright light to protect them. 

‌Snow blindness symptoms can appear hours or even up to a day after the initial eye damage happens. When your eyes get sunburned, you may experience:

  • Eye pain 
  • Watering eyes
  • Eye swelling
  • A headache
  • Seeing halos around bright lights
  • A gritty feeling in your eyes
  • Redness in your eyeballs and eyelids
  • Eyelid twitching
  • Pain when seeing bright light
  • Rarely, vision loss

‌Despite its name, snow blindness does not require snow to occur. It can happen after many different situations with bright sunlight or UV rays. 

Outdoor areas with many light-colored surfaces will reflect more UV rays. UV rays also get stronger the higher you are above the ground. Some machinery can also produce UV rays. 

You can get snow blindness from:

  • Being on snow-covered ground
  • Hiking high in the mountains
  • Being on a beach with white sand
  • Sunlight reflecting off the water
  • Tanning beds
  • Welding equipment
  • Light-colored concrete or pavement

‌Snow blindness can occur indoors and outdoors depending on what you are doing. Both natural and artificial UV rays can damage your eyes if you are not careful.‌‌

‌Snow blindness usually goes away on its own after a few days, like a sunburn. Try not to drive or operate heavy machinery if you’re experiencing snow blindness. Its impact on your vision can make those activities dangerous.

Spending too much time in the sun without eye protection can lead to more serious conditions:

  • Eye cancer
  • Cataracts 
  • Growths on the eyelid
  • Vision loss and farsightedness

Although now blindness can be painful, it is a temporary condition. You can take several steps to make healing easier and prevent further damage.‌

Take out your contacts. If you wear contacts, take them out of your eyes as soon as you notice symptoms. Don’t put them back in until symptoms have completely gone away.

Get indoors or into the shade. Since sunlight causes snow blindness, try to get somewhere that has lower lighting. Being in a dark room or shaded outdoor area will prevent further UV damage.

Use a cold compress. Put ice cubes in a plastic bag and wrap it with a paper or cloth towel. Place the covered bag on your closed eyes for 20 minutes. This can reduce pain and swelling.

Eye drops. Lubricating eye drops, also known as artificial tears, can help protect the surface of your eyes. You can use them to help reduce eye pain and dryness from snow blindness. You can find these at most grocers and drugstores. 

Pain relievers. Most over-the-counter pain relievers can reduce discomfort from snow blindness.

Talk to your doctor. If your symptoms worsen or don’t get better within 3 days, contact your doctor. They can help figure out why.

You can take simple steps to prevent snow blindness and protect your eyes.

Sunglasses and goggles. Wear UV-blocking sunglasses when you’re outdoors. Most sunglasses and sport goggles have UV filters, but older pairs might not fully block out harmful UV rays.

Avoid tanning beds. Tanning beds have many health risks for your eyes and skin. The UV rays they produce can be up to 100 times stronger than those from the sun. If you want tanned skin, opt for a spray or artificial tan instead.‌

Stay in the shade. Try to stay in shaded areas when you’re outside, especially between 10 a.m. and 4 p.m. Shaded areas block UV rays from the sun overhead. Although UV rays can still reflect off of light-colored surfaces, like snow, sand, or concrete, in the shade, they will be less damaging.‌

Wear a hat. Hats provide shade for your eyes no matter where you are outside. The most protective hats are dark-colored and made of canvas. Straw hats usually have holes that let through too much sunlight.