What it is
The eye keeps its shape thanks to a clear fluid that is constantly made and drained away. In glaucoma the drainage blocks up while the fluid keeps coming, so pressure inside the eye climbs. That pressure crushes the delicate nerve cells of the retina and the optic nerve, and once they are damaged, sight in that eye does not come back.
Some dogs inherit a narrow drainage angle in the eye; in others glaucoma follows another eye problem, such as inflammation or a displaced lens. When it is inherited, the second eye is at risk too.
Glaucoma causes a headache-like pain that can make a dog quiet, withdrawn or snappy when the head is touched. Dogs who lose their sight can adapt surprisingly well to a home they know: keep the furniture where it is, speak before you touch them and block off the stairs, and they will feel secure.
Signs you may notice
- Red, bloodshot eye
- Cloudy or bluish eye
- Eye looks bigger or bulging
- Squinting with a watery eye
- Rubbing the eye
- Bumping into things
The eye may look red, cloudy or bluish-grey, bulging and watery, and the dog squints, rubs the eye or shies away from having its head touched. If you see a red, cloudy, bulging or painful eye, don't wait: contact a vet right away.
When to see a vet
A red, cloudy, bulging or painful eye is an emergency: a vet is needed immediately, as sight can be lost very quickly.
This is general information, not veterinary advice. For your own dog's health, tests and treatment, see a vet.