hi there, conjuctivitis could be viral, bacterial,fungal or allergic in nature. Usually viral conjuctivitis is self limiting and resolves in a week or so. Bacterial conjuctivitis requires antibiotic drops for a week to ten days depending on the severity of the condition, fungal infections are very tenacious and need special attention and prologned course of anti-fungal agents. Allergic conjuctivitis persists as long as the offenting agent is around. Now if you are having persistent conjuctivitis either you are getting reinfected by bacterial agents due to improper hygiene,or may be due to use of infected contact lens, or you ahve fungal infecton with suboptimal treatment or it is allergic in nature and you need to pin point the allergen and get rid of it to get a permanent cure. Hope you understand all the information provided and take care.,