Pupils, the dark circles in your eyes, are usually equal in size.
Unequal pupils (anisocoria) may be a sign of a medical issue.
Or you might notice someone elses pupils are not the same size.

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Sometimes unequal pupils can be associated with other symptoms.
When one eye is exposed to light, the other eye also constricts.
Abnormal pupil size can be:
Causes
Some people are born with unequal pupils.
This can be a harmless physical feature or a sign of an eye or brain problem.
Babies with anisocoria should have an initial physical examination to determine whether a serious cause needs to be addressed.
Many illnesses can cause pupils to be unequal.
Causes of unequal pupils can include:
How Does Anisocoria Happen?
What is Horner’s syndrome?
Horners syndromeincludes a droopy eyelid, pupil constriction, decreased sweating, and possibly eye redness.
What Medications Can Cause Unequal Pupils?
Many medications affect pupil size and can cause anisocoria.
Many medications have the potential to cause changes in pupil size or anisocoria as a side effect.
These effects are usually symmetrical, but they may be unequal.
What drug causes unequal pupils?
Diagnostic tests are often needed as well.
Your healthcare provider will determine whether you have any visual problems.
Other symptoms and signs can help to identify underlying medical conditions.
Diagnostic tests may include:
Treatment
The treatment of unequal pupils varies.
In some circumstances, the pupil size can indicate a severe medical emergency.
Thats why prompt medical attention is necessary.
Treatment is not necessarily focused on making the pupils look equal.
Instead, the priority of treatment is to manage the underlying condition.
This can be a sign of a medical emergency.
The plan will include which symptoms you oughta call about and who to call.
Summary
Unequal pupils (anisocoria) has many different causes.
If you develop new anisocoria, its important to get medical attention.
The diagnostic process involves a detailed eye exam and neurological examination.
Treatment is necessary if your unequal pupil size has a medical cause.
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