Pink eye can last anywhere from 5 to 15 days, depending on the cause. Viral pink eye usually lasts about 7 days, but it may clear in around 5 days in people with stronger immune systems or take up to 12 days in children, older adults, or people with weaker defenses.
Bacterial pink eye lasts about 8 days on average. Symptoms may start to improve after the second day of antibiotic treatment, but the antibiotic should be used for the full time prescribed, even if the eye looks and feels better sooner. Stopping treatment early may leave bacteria behind.
Allergic pink eye can vary a lot. Symptoms often improve after about 2 days of using an antihistamine, but they can last up to 15 days if the person keeps being exposed to the allergy trigger or does not use the recommended treatment. Unlike viral or bacterial pink eye, allergic pink eye is not contagious.
Because viral and bacterial pink eye spread easily while symptoms are present, it is best to stay home from school or work and ask a doctor about when it is safe to return.