Dilating drops are used to dilate or enlarge the pupils of the eye to allow the Ophthalmologist to get a better view of the inside of the eye. It usually takes about 20-30 minutes for your pupils to fully open.
Dilating drops blur vision for a length of time which varies from person to person and may make bright lights bothersome. You will have trouble focusing on close objects. It is not possible for your Ophthalmologist to predict how much your vision will be affected. Because driving may be difficult immediately after an examination, it's best if you make arrangements not to drive yourself.
An adverse reaction, such as acute angle-closure glaucoma, may be triggered from the dilation drops. This is extremely rare and treatable with immediate medical attention.