Patanol Eye Drops (Olopatadine) is an ophthalmic solution which alleviates conjunctivitis (also called pink eye) caused by allergies. It works locally by blocking histamine activity in the eyes. Hay fever can often affect the eyes. This is known as seasonal allergic conjunctivitis, and it occurs when the tissue on the white part of the eye (known medically as the conjunctiva) becomes inflamed, causing it to become red, itchy and swollen. Blurred eyesight as well as watering of the eyes may also occur. In general, these symptoms are brought on by the body`s reaction to allergens, which may include pollen, grass, dust or other substances.