Small Pupil

Size of pupil is smaller than usual, this condition of Small pupils in pets (medically known as anisocoria) occurs when one pupil is smaller than the other. Normally, pupils will enlarge when there is little light present. However, when one or both remain small in the dark, it can indicate a problem with the eyes. Some of the most common causes of small pupils in dogs and cats include inflammation of the eye, pressure in the eye, cancer, scar tissue and various eye diseases.

Small Pupil

How to Recognize

If one or both pupils appear smaller than usual or do not dilate in the light, it can be a sign of an underlying issue.


Small pupils may be due to inflammation, increased pressure or built up scar tissue in the eye, cancer or a tumor, or an eye disease.


Your veterinarian will use an Ultrasound to search for any possible trauma and an MRI or CT scan to look for a growth that could be the cause of small pupils.

Small Pupil Affects

  • Dogs
  • Cats

Similar Symptoms

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