Is Pupil Dilation Bad for the Eyes?

What Is Pupil Dilation?

Pupil dilation uses medicine to fully relax the eye's ciliary muscles, so they can't adjust focus. This makes the pupils get bigger. After some time, the pupils will go back to their normal size. It's often used in eye checks and can also treat fake nearsightedness in teens.

Why Do We Need Pupil Dilation?

Kids have strong ability to adjust their eyes. Without dilation, the measured eye power would include a lot from this adjustment—what we call fake nearsightedness. After dilation, the eye muscles are relaxed, can't adjust, and the measured power is the real one.

What’s the Difference Between Rapid and Slow Dilation?

In clinics, there are two types: rapid and slow.

Rapid Dilation

For patients 12 and older, it uses compound tropicamide eye drops. The eye check is done 30 minutes later, with another check the next day. It's also used for anyone needing a fundus exam. After dilation, people often say they see blurry, especially close-up. This is because the pupils are bigger. Pupils usually go back to normal in 5–6 hours.

Slow Dilation

For kids under 12, it uses 1% atropine ointment. Put it on for 3 straight days, then do the eye check on the fourth day. Another check is done 3 weeks later, when the pupils will be back to normal.

Is Pupil Dilation Really Bad for the Eyes?

Dilation itself is not bad for the eyes. In fact, it helps relax the ciliary muscles when they're overworked.

But slow dilation uses atropine sulfate, which can cause side effects in kids, like red face, sweating, and fast breathing. Most of these don't last long and will get better soon. Parents should watch their kids closely, but these effects aren't serious.