Trinity is right. If you read the warning etc. on the medicine it states that you should have a baseline eye exam prior to TX. It is not real common but there have been cases of the TX causing serious eye problems. Get the eye exam. My personal recommendation would also be bring your sunglasses and it at all possible have someone drive you home. They will dilate your eyes. When I had mine done I went to drive home and the sun was in my eyes. Even with my sunglasses it was unbearable causing my eyes to tear up badly. I had pull over and wait to drive.
Everyone has or should have one done before starting tx. I had an eye exam. Tx can cause optical problems for some and they want to make sure eyes are ok