What is snow blindness?

The medical term for snow blindness is photokeratitis and means inflammation of the cornea.

You don’t have to be around snow to get snow blindness, but people who go skiing or snowboarding for example, spend time at high altitudes where UV rays are stronger and are surrounded by snow, which is a highly reflective surface. Without wearing the right sun protection, this can increase the chances of getting photokeratitis. Water and white sand can also have the same effect.

Causes of snow blindness

Light enters our eyes through the cornea, which is the eye’s outermost transparent layer. Photokeratitis happens when the sensitive surface layer of the cornea becomes inflamed due to an overexposure of UV light.

Harmful UV light can come from the sun, or from artificial light produced in things like tanning beds, sun lamps, lasers, and welding equipment.

People who spend a lot of their time outdoors might be more likely to develop photokeratitis, particularly without wearing sufficient eye protection.

Symptoms of snow blindness

How long do the symptoms last?

In a similar way to when your skin is sunburned, you might only notice snow blindness symptoms a few hours after you’ve been in the sun. Symptoms can seem quite alarming, but they should go away on their own after 24-48 hours, after which your eyes will be back to normal.

If you’re concerned about your symptoms, you should see your optometrist to examine your eyes and look out for signs of other potential eye conditions.

Snow blindness treatment

Snow blindness treatment involves staying inside and giving your eyes plenty of rest. Once you give your eyes a break from UV light outside, your eyes should start to improve quite quickly.

There are a few things you can try to relieve your symptoms:

  • Rest in a darkened room
  • Stop wearing contact lenses until a few days have passed with no symptoms
  • Use moisturising eye drops
  • Avoid rubbing your eyes
  • Put a cold cloth over your eyes

See your optometrist if your symptoms get any worse, or don’t go away after a couple of days. Your symptoms may be an indication of a different eye condition.

How is snow blindness (photokeratitis) diagnosed?

Recent history of excessive exposure to UV, either from the sun or artificial sources, combined with corneal swelling seen on examination, is usually enough to diagnose photokeratitis.

Eyecare professionals such as optometrists, ophthalmic nurses and ophthalmologists are in the best position to make this diagnosis and to rule out other problems.

How to prevent and avoid snow blindness

The good news is that snow blindness can be prevented very easily and wearing proper eye protection is all it takes to avoid snow blindness.

Be mindful that it doesn’t have to be clear skies and bright sunshine for your eyes to be affected by UV rays, so it’s important that you wear eye protection if you’re outdoors for a long period of time. You could also try photochromic (Reactions) lenses that adapt to changing light going in and out of doors.

If you regularly go skiing, snowboarding or take part in water sports you should invest in some snow or sports goggles with a wraparound design for full eye protection.