Dilated pupils are when the dark center of your eye is widened.
This happens naturally in dim setttings.
It can also happen after taking certain medications or drugs.
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In both of these situations, dilation is temporary.
Dilated pupils that don’t turn back to their regular size, however, are not normal.
Radu Bighian / Getty Images
What Are Dilated Pupils?
Dilated pupils happen when the black circles in the colored part of your eye (iris) gets larger.
What Is Anisocoria?
Anisocoria is when one pupil is dilated, rather than both.
Causes of Dilated Pupils
Your pupils often dilate naturally in response to the light in your environment.
Other reasons they can dilate include:
Natural Response to Light
Your pupils allow light to enter.
This could help you notice if your pupils are not their usual size or are reacting abnormally.
When tested, the pupils will not respond normally to light-related stimuli.
Notably, they will not constrict when the eye is exposed to a large amount of light.
Pupils will return to normal as the effect of the drug wears off.
It takes about 20 minutes to 30 minutes for the drops to work.
Injuries
Trauma to the eye or the braincan also cause dilated pupils.
It can also causebleeding inside the skull, which can make the pupils enlarge.
Your pupils might get bigger when youre feeling attraction or have an emotional response to someone or something.
Sometimes, dilated pupils are just temporary and get better without issue.
They can figure out whats causing your pupils to be dilated and verify you get the right treatment.
Frequently Asked Questions
They can.
Your pupils can dilate when you have higher levels of oxytocin.
Oxytocin (the “love hormone”) increases when you are emotionally aroused.
No, it’s usually the opposite.
If you are tired or sleepy, your pupils will likely be smaller than usual.
Stress can cause your body to activate the sympathetic nervous system.
This triggers a fight-or-flight response and can cause dilated pupils.
It depends on what’s causing them.
If medication is the cause, your doctor may recommend switching to another drug.
Your doctor may suggest special contact lenses or sunglasses to reduce light sensitivity from dilated pupils.
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