Eye drops can be used to treat many symptoms that affect the eyes, including itchiness, burning, redness, excessive watering, infections and discharge. Such symptoms can be caused by a variety of conditions including chronic dryness, allergies and eye infections.

Eye drops are also used during eye examinations to dilate the pupils, and to treat serious eye disorders such as glaucoma (a disorder that involves optic nerve damage). They can deliver a variety of medications directly to the eye tissues, preventing or relieving symptoms directly where they appear. Many eye-related conditions affect the conjunctiva, the clear tissue that covers the white of the eye and the inner eyelid. The conjunctiva contains many mast cells, which play a prominent role in triggering symptoms of an allergic reaction.

Patients who use eye drops should follow several steps to ensure that the medication gets into the eye and is fully absorbed. As with any drug, eye drops should not be used unless a physician approves their use.