Each contact lens brand that makes disposable lenses has their suggested replacement time frame, which is also specified by Health Canada. All of Johnson & Johnson Acuvue brand lenses are to be replaced every 2 weeks except for their 1 day lenses. Other brands such as Coopervision, Cibavision/Alcon and Bausch & Lomb typically have their replacement set at 1 month. This means that once the lens foil pack has been opened it should be disposed of after month.