It is important to have a “backup” pair of glasses in case you could not wear your contacts for any reason. If you were to lose or tear a lens, you should have glasses to wear until you could get a replacement. Also, if your eyes ever get red, itchy, irritated, or have any discharge, you should take your contacts out and wear glasses until you can be seen by an eye doctor. You should not wear contact lenses when you are sick (i.e. with a cold or flu) because you have an increased risk of spreading that infection to your eyes.