eye drop eye drop eye drops or eyedrops are liquid drops applied directly to the surface of the eye usually in small amounts such as a single drop or a few drops. eye drops usually contain saline to match the salinity of the eye. drops containing only saline and sometimes a lubricant are often used as artificial tears to treat dry eyes or simple eye irritation such as itching or redness. eye drops may also contain one or more medications to treat a wide variety of eye diseases. depending on the condition being treated, they may contain steroids, antihistamines, sympathomimetics, beta receptor blockers, parasympathomimetics, parasympatholytics, prostaglandins, nonsteroidal anti-inflammatory drugs (nsaids), antibiotics, antifungals, or topical anesthetics.