It depends- on the type of contact lenses you wear and how your eyes respond to the reduced oxygen supply.
Never wear contacts when sleeping, even for short naps, if your lenses are not FDA-approved for overnight (“extended wear”) lenses, but they block too much oxygen from the eye to be worn during sleep.
Even if your contacts are approved for overnight wear, this doesn’t guarantee your eyes will tolerate wearing them while sleeping. Your eyes may be too dry or too sensitive for overnight wear, which could lead to discomfort, blurred vision or even a serious eye infection.
There’s only one way to know for sure if you can wear contacts safely during sleep: Ask your eye doctor to evaluate how your eyes respond to overnight wear with lenses that are FDA-approved for continuous night-day wear.