Eye dilation is a term that means opening your pupils with special drops. The eye drops make the pupils larger so the eye doctor can better view the internal structure at the back of your eye. It usually takes around 20 minutes for the drops to start working, but the effects are temporary and wear off after two to three hours. While your pupils are dilated, you will be more sensitive to light. If you don’t have your sunglasses with you, the eye doctor will give you special ones when you leave. You may also have difficulties focusing on objects or reading.

Most eye doctors agree that this test is one of the critical components of a comprehensive eye exam. Examining eyes while the pupils are dilated allows detection of conditions like diabetes, macular degeneration, cataracts, glaucoma, and more.


When your pupils are dilated it is much easier for your doctor to examine your optic nerve. This helps diagnose glaucoma, as well as any other abnormalities with the nerve.

Macular Degeneration

Macular degeneration is a very common age-related retina disease.

Other Conditions

Not only glaucoma and macular degeneration can be detected with the exam, there are multiple conditions that need pupil dilation to be found, such as an ocular tumor, retinal tear or detachment.

When You Should Have The Test

If you don’t suffer any chronic diseases, the frequency of the test depends on your age. For people under 18 it’s recommended to perform dilated tests every year. It’s necessary to diagnose any eye disease so it doesn’t become advanced and then chronic. For example, if lazy eye is not detected early, by age nine, the condition can lead to a limited vision that will be impossible to correct.

If you’re somewhere between 18 and 80, you may have the exam every two years. However, when you get older, your risks increase, as does the frequency of the test. In this case, the yearly test is recommended.

Is It Possible To Have An Exam Without Dilated Eyes?

It is possible to examine for these conditions without dilating the pupils. Some health clinics, pediatrician’s offices, and local health organizations may not even perform eye dilation. They conduct basic tests, but they won’t help you diagnose serious eye diseases and can’t substitute for a thorough eye exam from a skilled professional. Most doctors will tell you that dilating your pupils is the best way to perform a thorough the eye exam.