Submitted by Karen Saland on Mon 06/10/2019 - 02:22
Eye dilation is a key component of a comprehensive eye exam. Dilating eye drops contain medication to enlarge (dilate) the pupil of the eye. There are two types of drops: one type stimulates contraction of the muscles that enlarge the pupil (phenylephrine); the other type relaxes the muscles that make the pupil constrict and also relaxes the muscles that focus the lens of the eye (cyclopentolate). These two kinds of medications are often used together, either as two separate drops or as a single combination drop.
During a comprehensive eye exam in Dallas, having your eyes dilated allows Dr. Saland to closely examine the inside of the eye in order to diagnose and treat eye diseases. Also, relaxing the focusing muscles of the eye allows for a more accurate measurement of refractive error (the need for vision correction).
Once the dilation drops are administered, it normally takes 20–30 minutes for the eyes to fully dilate. It then just takes 5–10 minutes for the eyes to be examined. The pupils will remain dilated and larger than normal for 4 to 24 hours, depending upon the strength of the drop and upon the individual patient. During this time your vision may be slightly blurry and you will experience increased light sensitivity.
Pupil dilation tends to last longer in people with lighter colored eyes since brown pigment in the iris is essentially the only eye pigment, blue eyes lack significant color and gain their blue shade from light reflecting in the iris. Pigment binds the dilating drops and require higher doses, but blue eyes react faster and more to dilation drops. Occasionally a child’s eyes may stay dilated for longer than 24 hours.