When your pupils are small, this condition is medically called miosis or pinpoint pupils. It means the pupils are constricted or abnormally small, typically less than 2 millimeters in diameter

Common causes of small pupils include:

• Bright light exposure: Pupils naturally constrict in bright light to limit the amount of light entering the eye

• Medications and drugs: Certain prescription drugs (like those for anxiety, muscle spasms, seizures) and illicit drugs (such as opioids) can cause pupil constriction

• Eye or brain injury: Trauma to the eye or head, including concussion or internal hemorrhage, may cause small pupils

• Neurological conditions: Conditions like Horner’s syndrome, brainstem stroke, or nerve damage can lead to abnormally small pupils

• Eye inflammation: Inflammation inside the eye (iritis or uveitis) can cause pupils to constrict due to pain or irritation

• Aging: Pupils naturally get smaller with age and may respond slower to changes in light

• Other health issues: Rare conditions such as Adie’s tonic pupil, cluster headaches, or late-stage syphilis can also cause small pupils

When small pupils may indicate a serious problem:

• If accompanied by symptoms like dizziness, balance problems, slurred speech, or vision changes, it could signal a stroke or neurological emergency

• After a head injury, abnormal pupil size warrants urgent medical evaluation

• Persistent small pupils with eye pain or vision disturbances should be assessed by a healthcare professional

In summary, small pupils can be a normal response to light or aging, but they can also indicate drug effects, eye or brain injury, or serious neurological conditions requiring medical attention