This type of disposable lens is designed to be worn during waking and sleeping hours for a number of consecutive 24 hour periods, generally not more than six. While EW lenses are very convenient for many lens wearers, they aren’t tolerated by all. Customers who require the transmission of consistently high levels of oxygen to the corneal surface due to illnesses such as diabetes, certain medications or because of low levels of tear production may not be suited for EW lenses.
The FDA approved EW lens usage for up to 6 consecutive nights.
Continuous wear lenses are similar to EW lenses in terms of material, ease of use and comfort. However, they are designed for use for up to 30 consecutive nights or 31 days. As with extended wear lenses, this product isn’t suitable for all CL wearers, and should only be used in consultation with an eye care specialist after review of health conditions.