Clygan Eye Ointment is an antiviral medicine used to treat viral infections caused by cytomegalovirus in immunocompromised people who have undergone an organ or bone marrow transplantation. It also reduces the risk of blindness in a serious eye infection caused by CMV, known as CMV retinitis. Clygan Eye Ointment is for external use only. Take it in the dose and duration as advised by your doctor. Wash your hands before and after applying the medicine. Hold the tube close to the eye without touching it. Gently squeeze the tube and place the medicine inside the lower eyelid. It may cause eye irritation immediately following application. However, this side effect is temporary and usually subsides on its own. Inform your doctor if it persists for a longer duration. Do not wear contact lenses while using this medicine.