How Long For Dilated Eyes To Return To Normal?

We get it; it’s annoying to have the eyes dilated. But having your eyes dilated is a necessary evil when you see the eye doctor. Dilation can cause your vision to become blurry and will cause everything to be super bright. But this dilation won’t last forever. In fact, it may not even last the rest of the day.

For most people dilated in the office, eye dilation lasts between 4 and 6 hours. Dilation for other purposes, such as for surgery, can take about a day or longer to wear off and for the eyes to return to normal.

Ophthalmologists and optometrists use different eye drops to dilate the eyes for different purposes. These different eye drops work for different amounts of time.

Of note: if your eye is suddenly dilated and you didn’t have any eye drops, seek medical attention

Most common standard eye dilation

The most common situation which calls for the eyes to be dilated is during an eye exam. Short-acting eye drops are used for this purpose. This includes the eye drops tropicamide & phenylephrine. These short-acting eye drops will last between four to six hours for most people.

Dilating drops are used during an eye exam for two main purposes:

Diagnosis

Taking a good look at the back of the eye.

In the back of the eye is the retina. If the eye is like a camera, the retina is like the “film” (or image sensor since everything is digital nowadays). It records incoming light and sends signals to the brain to process that light.

But without dilating the eyes, its difficult to get a good view of the retina. There is only a tiny hole (the pupil) to look through and see the retina. Dilating the eyes allows the pupil to get very large so that eye doctors can get a great view and ensure the retina is healthy.

Measuring prescription

Getting the most accurate prescription possible.

In addition to dilating the eyes, certain dilating drops also perform one other function. Certain drops (such as tropicamide) prevent our natural lens from focusing. At baseline, our natural lens is flexible and able to seamlessly focus from off in the distance and up close (unless you’ve entered the ages of presbyopia and are starting to lose this ability).

But this flexibility and focusing ability of our lens allows us to focus through extra prescription during an eye exam. This can lead to inaccurate measurements. Thus eye drops are added to prevent this lens from focusing in the short term during your eye exam.

(This is why it’s harder to see up close when your eyes are dilated)

Dilation for surgery or symptom relief

This often calls for a little more powerful dilation. For these purposes, a intermediate-acting dilating eye drop may be used: Cyclopentolate.

Dilation with this longer-acting eye drop last about 24 hours for most people.

Surgery

For any surgery where the surgeon needs to look past the iris, dilating drops are used. This includes cataract surgery and retina surgeries.

Having a great view makes the surgery as smooth as possible for the surgeon. Sometimes, the standard short-acting dilating drops may not be as effective in dilating the patient’s eye. And also, sometimes dilation can wear off in the middle of a surgery. To ensure the best view, the surgeon may want to use eye-drops that will have a harder time wearing off. This calls for the intermediate-acting eye drops. That extra few hours of being dilated can be worth it to ensure that the surgery is a success.

Treatment of inflammation within the eye

Certain conditions can cause sudden inflammation within the eye called iritis (inflammation of the iris). This causes light sensitivity and discomfort.

The most common treatment for inflammation within the eye is steroids. But until the steroids take effect, it’s important to also help improve the light sensitivity and discomfort.

When light shines in the eye, it causes the iris to constrict and the pupil to get smaller. When the iris is inflamed from iritis, this movement of the iris muscle is uncomfortable.

Intermediate-acting dilating drops are frequently added to the steroid treatment to prevent the iris muscle from moving. This improves the sensitivity to light by preventing the iris from constricting whenever light is shown in the eye. The iris stays dilated and motionless.

Your eye will stay dilated for as long as you are taking the dilating drop; but your eye will feel more comfortable.

Accurate prescriptions in kids

If dilating drops are important in adults to get accurate prescriptions, they are even more important in kids. Kids have a very strong focusing ability of their lens. This extra strong focusing ability requires more powerful eye drops. Intermediate-acting eye drops are frequently given at pediatric eye appointments (most often mixed together with the short-acting drops; since it’s not easy to put eye drops in kids).

The long-acting drops

Finally, the dilation drop that last the longest is atropine.

This dilation drop will last one week!

Given how long this dilation drop lasts, there are limited use cases for this eye drop. Similar to the intermediate-acting drops, it can be used to treat inflammation (especially when it’s known that the inflammation will take a long time to recover).

Atropine eye drops get a little more frequent use in kids. It can be used to help treat a lazy eye or ambylopia. Low-dose atropine is also being explored as an option to prevent kids from becoming more nearsighted over time.

Can anything be done to reverse dilation quicker?

There used to be an eye drop called “Rev-Eyes” which could help reverse the dilation. The problem is that this drop didn’t work very well. As such, the drop is no longer available.

There are no eye drops which can reverse dilation.

Technically, however, there are medications which can be used during surgery to reverse the dilation. These eye drops are occasionally used at the end of a surgery case to make the pupil smaller. The trouble with these eye drops is that sometimes they work too good. You can reverse the dilation too much and get too small of a pupil. This can also cause blurry vision and difficulty adapting to low light situations. Often it’s just better to leave the eye dilated and allow it to naturally return back to normal.

Summary

When you see the eye doctor, it will take about 4-6 hours for dilated eyes to return to normal after eye dilation. There are a few situations, such as surgery and treatment of some eye conditions where the eye dilation can last up to a day or longer. But no matter the eye drop, eye dilation from eye drops will eventually wear off.