Sleeping in Contact Lenses: Risks, Symptoms, and Complications

Your eyes need a constant flow of oxygen for healthy functioning. When you wear contact lenses overnight, the natural oxygen supply to your cornea is drastically reduced. Here’s the thing: closed eyelids already reduce oxygen exposure by limiting airflow, and contact lenses only add another barrier. As a result, your cornea may swell up, sometimes by as much as 4% even during regular sleep without lenses. When you combine that with the added barrier of a contact lens, the decrease in oxygen can be even more pronounced, setting the stage for a host of complications.

The lack of oxygen, or hypoxia, can kick off several undesirable conditions. Foremost among these is the increased risk of eye infections. Studies have found that the odds of developing an infectious keratitis or corneal infection can be four to five times higher for someone who sleeps in their lenses compared to those who wear them only during the day. What does that mean for you? It signifies that even if you feel no immediate discomfort, your eyes are at risk for serious infections that can lead to long-term complications if not addressed promptly.

Our eye doctors emphasize prevention and care, urging patients to avoid the habit of sleeping in contact lenses unless specifically prescribed under special circumstances. The environment created under a closed lid and a lens is particularly favorable for bacterial growth, with types like Pseudomonas capable of causing aggressive infections that damage the cornea rapidly. Reducing the time your eyes are deprived of oxygen is essential for preventing these outcomes.