No, contacts are not available for everyone. First of all, people who have some eye diseases cannot wear contacts, such as people with conjunctivitis, keratitis, trachoma, dacrycystitis, and those who got their lacrimal passage blocked, who has low secretion of tears, who are monocular, and so on. Secondly, people who have systemic diseases such as serious nervousness, sensitive to eye hurt, nasosinusitis, gestation, diabetes mellitus, etc., cannot wear contacts. When people are in abominable conditions such as sandy and windy, dusty, and volatile acid-bases should not wear contacts in case of eye infection. And contacts are especially not available for adolescents. They are still in the period of upgrowth, and wearing contacts will lead to their cornea anoxia as well as impediment in physical metobolic. In addition, people who are more than forty years old should gradually give up wearing contacts, because their eye organizations begin to degenerate at this age, and the ability of the eye balls to endure anoxia also degenerates. People whose age are between 40 and 60 can only wear contacts for a short time if must. And people who are over 60 years old should better wear prebyopic glasses.
