Photokeratitis is essentially a sunburn of your eyes caused by intense ultraviolet light exposure.

Countries & Cities · Published 15 October 2026 · Updated 25 October 2026 Swipe more like this →

In short: Often called snow blindness or welder's flash, this painful condition occurs when your eyes are exposed to excessive UV radiation. While symptoms like redness, light sensitivity, and a gritty sensation usually resolve within 48 hours, the damage can be severe, highlighting the importance of proper eye protection in bright environments.

Photokeratitis is a temporary but painful injury to the surface of the eye resulting from overexposure to ultraviolet light. It functions much like a sunburn, where the cornea sustains damage from UV-A and UV-B rays. While the ozone layer effectively blocks harmful UV-C radiation, other sources—both natural and artificial—can trigger the condition. Common culprits include sunlight reflected off snow, ice, sand, or water, as well as industrial hazards like arc welding, tanning beds, and certain types of lamps.

The symptoms typically manifest between six and 24 hours after exposure. Patients often report intense eye pain, tearing, blurry vision, swelling, and a distressing sensitivity to light. In rarer instances, individuals may experience halos, headaches, or even temporary vision loss. While the condition is generally self-limiting and usually disappears within 48 hours, the discomfort is significant. Medical professionals may use lubricating drops or pain medication to manage symptoms, though they caution against the overuse of anesthetic drops, which can potentially lead to corneal ulceration.

Prevention remains the most effective strategy. Sunglasses that block nearly all UV rays and transmit only 5–10% of visible light are recommended, ideally featuring side shields to prevent incidental exposure. Historically, indigenous peoples in circumpolar regions developed ingenious solutions, such as carving snow goggles from driftwood or caribou antlers to limit light intake. Explorers have similarly employed various methods, from using narrow-slit goggles to darkening the skin around the eyes with charcoal to reduce glare. Beyond immediate relief, long-term UV exposure is a cumulative risk factor for serious conditions like cataracts and macular degeneration, making consistent eye protection a vital habit for long-term ocular health.

General information, not professional advice. Spotted an error? Flag the card or see corrections and complaints.

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