Can I use Visine on my 5-year-old?

It would be best to find out why your child has red and itchy eyes and to treat that cause. In a child, red, itchy eyes can be caused by allergy, infection (either viral or bacterial), a foreign body in the eye, a scratch, or blepharitis. Using Visine over a long period may lead to "rebound hyperemia" where the eye gets red a few hours after the drops—even redder than when you started. Please schedule an appointment with a pediatric ophthalmologist who can evaluate your child and provide treatment.