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Hypothyroid Overview

Hypothyroid Overview

The thyroid gland produces essential hormones that are involved in the regulation of many vital body functions. Hypothyroid pets produce too little of these important hormones.

Hypothyroidism usually develops gradually and can easily be mistaken as laziness or "slowing down" from age or obesity. This disease is rare in cats.

Pets may exhibit one or many common signs, including:

  • weight gain
  • reduced activity
  • decreased energy
  • heat seeking behavior
  • dry and flaky skin
  • chronic skin and ear infections
  • hair loss
  • darkening of skin pigmentation
  • droopy or sad facial expression

Diagnosis is based on symptoms, examination findings and blood work that includes testing the level of thyroid hormone present.

Treatment usually consists of medication that replaces the missing thyroid hormone. After placing a pet on replacement hormone, the thyroid level must be checked 1-2 months later, after any medication adjustments, and occasionally thereafter to ensure proper dosing.

Concurrent problems, such as skin or ear infections, will need appropriate treatment as well.

Many pets on replacement hormones gain energy, begin to lose excess weight, and have improvements in skin or ear problems. They often appear to feel better in general.


  • Use all medications as prescribed by your veterinarian.
  • Your pet will need thyroid hormone level checks as directed by your veterinarian.
  • Monitor your pet's progress carefully and have him or her rechecked if you have any concerns.

If you have questions about this or any medical topic, please contact your Banfield hospital today.