Pupils, the tiny black openings in the center of our eyes, are essential in regulating the amount of light reaching the retina. By dilating or contracting, they enable optimal vision in different light conditions. However, when pupils remain dilated for no apparent reason, this can raise questions.
Why do pupils dilate?
Pupil dilation is the body's natural response to various stimuli. Here are some common causes:
• Dim light: In darkness, the pupils dilate to let in more light and improve night vision.
• Strong emotions: Fear, excitement, or other intense emotions activate the sympathetic nervous system, which can temporarily dilate pupils.
• Medication: Some eye drops for eye examinations contain mydriatic agents that temporarily dilate the pupils. Antidepressants, antihistamines and stimulants can also have this effect.
• Recreational substances: Drugs such as cocaine, amphetamines, or LSD can induce prolonged pupil dilation.
• Trauma or injury: Injury to the head or eye can cause unilateral or bilateral pupil dilation.
• When to be concerned
Although dilated pupils are often benign, they can also indicate an underlying health problem. You should consult an Optometrist if you notice:
• Persistent dilation of the pupils, even in bright light.
• Dilated pupils are accompanied by symptoms such as intense headaches, blurred vision or dizziness.
• A difference in pupil size (anisocoria) with no apparent explanation.
These signs could be linked to high intracranial pressure, optic nerve damage or neurological diseases.
How are dilated pupils treated?
Treatment of dilated pupils depends on their cause:
• Temporary cause: No treatment is necessary when dilation is due to eye drops or dim light. Pupils will return to their normal size once the stimulus has disappeared.
• Medical problem: If dilation is linked to an underlying problem, targeted treatment, such as medication, surgery, or neurological management, will be required.
• Protecting the eyes: Wearing sunglasses may offer relief from light sensitivity due to prolonged dilation.
Prevention and follow-up
To minimize the risks associated with dilated pupils, it is important to:
• Avoid self-medication with non-prescription eye drops.
• Protect your eyes from trauma during sports or professional activities.
• Consult an Optometrist regularly, especially if you have an eye-related medical history.
Pupil dilation is often normal and transient but can also reveal more serious conditions. Stay alert to this and consult an Optometrist for your annual eye exam to preserve healthy vision. If you have concerns about your pupils or any other aspect of your eye health, don't hesitate to make an appointment with an eye doctor.
