Contact lenses are worn by millions of people every day and are often treated as harmless accessories rather than medical devices.
Because problems do not usually appear right away, risky habits can develop unnoticed.
Eye specialists warn that misuse of contact lenses is one of the most common and preventable causes of serious eye infections.
A public health concern
Ophthalmologists and public health bodies, consistently advise that contact lenses must be used exactly as prescribed.
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Daily disposable lenses are designed for single use and should be removed before sleep.
Wearing them for longer reduces oxygen to the eye and creates an ideal environment for bacteria.
Medical research shows that sleeping in lenses or reusing disposables greatly increases the risk of corneal infections, such as microbial keratitis.
These infections can progress quickly, causing pain, discharge, blurred vision, and in severe cases, permanent sight loss.
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Doctors note that many patients delay seeking help because early symptoms can seem mild.
When guidelines are ignored
The risks became very real for a nurse from Essex who temporarily lost vision in one eye after repeatedly wearing daily disposable lenses for days and sometimes weeks at a time. What began as occasional overnight use gradually became routine.
In August 2025, she developed sudden, severe eye pain and significant vision loss. Doctors were initially uncertain whether her sight would recover.
Although her vision eventually returned, clinicians involved said the outcome could easily have been far worse.
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Prevention matters most
Eye health experts stress that most contact lens–related injuries are avoidable. Their core advice includes: never sleeping in lenses unless specifically prescribed
The case has renewed calls for better awareness around contact lens safety. Used correctly, lenses are safe. Used carelessly, they can cause lasting damage.
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