Cyclopen D Eye Drop is used before eye examinations and for treatment of an eye condition called uveitis. It works by enlarging the pupil of the eyes and helps the doctor visualize the eye more closely. It also reduces redness and swelling in the eyes after cataract surgery. Cyclopen D Eye Drop is for external use only. Use it in the dose and duration as advised by the doctor. Refrain from touching the tip of the dropper to avoid contaminating the eye drops. Using Cyclopen D Eye Drop can make your eyes more sensitive to light. Thus, wear sunglasses to protect your eyes from sunlight and other bright lights. The common side effects include burning sensation, irritation, or temporarily blurring of the vision. Usually, these symptoms resolve quickly. However, if the symptoms persist for a longer duration, contact your doctor. It is not advised to drive after using this medicine as it may cause blurring of the vision.