Q. What is eye pressure (IOP) and what counts as normal?

Intraocular pressure is generated by aqueous humor, a clear fluid continuously produced inside the eye and drained through a mesh-like channel called the trabecular meshwork. When production and drainage stay balanced, pressure sits in the statistically normal range of 10 to 21 mmHg, averaging 15 to 16 mmHg. Eye pressure normal levels are not a fixed number for everyone; your ophthalmologist compares your reading against your corneal thickness, optic nerve appearance, and personal risk factors rather than judging a single value in isolation.

Q. What are the symptoms of high eye pressure?

• Usually no symptoms at all in chronic open-angle glaucoma, which is why it is often called the silent thief of sight
• Gradual, painless loss of peripheral vision noticed only after significant damage has occurred
• In acute angle-closure attacks: sudden severe eye pain, headache, blurred vision, and halos around lights
• Nausea, vomiting, and a red, hard eye during an acute angle-closure episode

❓ Frequently Asked Questions

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