Atropine Sulfate is used in the eye to dilate the pupil. This effect is useful in reducing pain after cataract surgery or eye injury and is also useful in treating glaucoma. Because atropine dilates the pupil, animals will be very sensitive to sunlight and should be kept out of bright light while receiving this drug. Horses will usually receive atropine sulfate as an ointment once daily or as a solution administered through an eye catheter. Contains 1% opthalmic ointment packaged in a 3.5 gram tube.