Table of ContentsView AllTable of ContentsSymptomsTypesCausesDiagnosisTreatmentWhen to See a Provider
Table of ContentsView All
View All
Table of Contents
Symptoms
Types
Causes
Diagnosis
Treatment
When to See a Provider
Pupils, the dark circles in your eyes, are usually equal in size. Unequal pupils (anisocoria) may be a sign of a medical issue.
You might notice that your pupils are not the same size when you look in the mirror. Or you might notice someone else’s pupils are not the same size.
Sometimes unequal pupils can be associated with other symptoms.
Symptoms that can be associated with unequal pupils include:
Types of Unequal Pupils
The pupils of the eyes normally constrict (get smaller in size) in response to light and when looking at near objects. These responses should occur symmetrically (the same for both eyes), even when someone naturally has a slight difference in the size of their pupils. When one eye is exposed to light, the other eye also constricts.
Abnormal pupil size can be:
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?Horner’s syndromeincludes a droopy eyelid, pupil constriction, decreased sweating, and possibly eye redness. It occurs due to conditions such as tumors, upper spine disease, stroke, disease in the neck or chest, and MS, which can affect sympathetic stimulation of the nerves that control the pupils.
What is Horner’s syndrome?
Horner’s syndromeincludes a droopy eyelid, pupil constriction, decreased sweating, and possibly eye redness. It occurs due to conditions such as tumors, upper spine disease, stroke, disease in the neck or chest, and MS, which can affect sympathetic stimulation of the nerves that control the pupils.
What Medications Can Cause Unequal Pupils?
Many medications affect pupil size and can cause anisocoria. Some of these are placed in the eye for the purpose of dilating (enlarging) the pupils as part of an eye examination or a surgical eye procedure. Many medications have the potential to cause changes in pupil size or anisocoria as a side effect.
A few of the medications that can cause unequal pupils include:
In addition to medications, some recreational drugs may also cause changes in pupil size. For example, using alcohol, marijuana, or cocaine can cause dilated pupils, and opiates can cause pupillary constriction or dilation. These effects are usually symmetrical, but they may be unequal.
What drug causes unequal pupils?The effects of medications or drugs on pupil size are temporary and wear off within minutes, hours, or days. It depends on the drug, dose, and a person’s ability to break down and remove the drug from the body.
What drug causes unequal pupils?
The effects of medications or drugs on pupil size are temporary and wear off within minutes, hours, or days. It depends on the drug, dose, and a person’s ability to break down and remove the drug from the body.
Diagnosis of the cause of unequal pupils involves a comprehensive physical examination, including an eye examination and a neurological examination. Diagnostic tests are often needed as well.
Your healthcare provider will determine whether you have any visual problems. They will also define whether you have fixed or reactive pupils and whether either of your pupils is dilated or constricted.
Other symptoms and signs can help to identify underlying medical conditions. For example, a severe headache may indicate increased intracranial pressure, while fever and stiff neck are signs of meningitis.
Diagnostic tests may include:
The treatment of unequal pupils varies. In some circumstances, the pupil size can indicate a severe medical emergency. That’s 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.
Some of the treatment options include:
When to See a Healthcare Provider
You should see a healthcare provider immediately if you suddenly develop unequal pupils. This can be a sign of a medical emergency.
Discuss a plan of action with your healthcare provider if you have a chronic condition that can cause unequal pupils, such as MS or a ventricular shunt. The plan will include which symptoms you need to call about and who to call.
Summary
Unequal pupils (anisocoria) has many different causes. It can be a natural physical trait, a temporary effect of medication, alcohol, or illicit drugs, or a sign of neurological or eye disease.
If you develop new anisocoria, it’s 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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