Common signs include
Thyroid hormones control the speed of your cat's metabolism, but when in excess, can cause a range of signs. The more thyroid hormone produced, the higher the metabolic rate and the more calories your cat burns.
Not all of these signs will occur in every cat with hyperthyroidism.
Poor body condition is
a common sign of
hyperthyroidism.
Hyperthyroid cats
might be nervous
or aggressive.
An enlarged thyroid
gland is sometimes
visible but more often
can be felt.
* Photographs: Courtesy of Dr Hans Kooistra, Utrecht University