What causes irritation and mucous discharge when wearing contacts?

Redness, itching, mucous discharge, and foreign body sensation in one or both eyes can indicate that a contact lens does not properly fit. You should not persist with a contact lens that causes these symptoms. Have your fit reevaluated and try different types of lense.  In many cases, modern oxygen-permeable rigid ("hard") contact lenses are kinder to one's eyes than soft contact lenses because they are small and do not irritate the transparent membrane that covers the white part of your eye.