The longest any lens in the United States is cleared to be worn continuously by the FDA is 30 days. However, most doctors recommend you take them out when you sleep, or at least once a week, just to be safe. However, not all contacts are designed the same – meaning 30 days is not the norm. Check with your doctor or eye care specialist or manufacturer to understand the limitations of your contacts. As a general rule, the more frequently you take your lenses out, the lower the risk of irritation, infection or damage to the eye. Some disposable lenses are to be tossed every night.