Mary Allen
Although the thyroid is very small, it is a vital organ. Over- or under-functioning can have serious consequences for cats. Learn how to recognize thyroid disease in your cat and how to treat it.
Although the thyroid is very small, it is a vital organ. An over-or under-function can therefore have serious consequences for cats. Learn how to recognize thyroid disease in your cat and how to treat it.
Hyperthyroidism In Cats
Overactive thyroid (hyperthyroidism) is the most common hormonal disorder in cats over the age of eight and is also significantly more common than underactive. Hyperthyroidism leads to unilateral or bilateral enlargement of the thyroid lobes, which in many cases is caused by a benign tumor.
Due to the enlargement of the thyroid gland, more hormones are produced, there is an oversupply and the cat’s metabolism is driven to peak performance. The onset of hyperthyroidism is still quite mild, with the following symptoms appearing or increasing as the disease progresses:
- increased appetite with simultaneous emaciation
- shaggy fur
- irregular hair loss
- increased water intake
- increased urination
- increased activity, restlessness
- nervousness to aggressiveness
The veterinarian makes the definitive diagnosis with a blood test. Differential diagnoses – diseases with similar symptoms – include, for example, diabetes mellitus, chronic kidney failure, or diseases of the pancreas. Therefore, every senior cat from the age of eight should have regular health check-ups to identify potential diseases at an early stage.
Treatment Of Hyperthyroidism In Cats
If the overactive thyroid gland is not treated, it leads to damage to the heart, kidneys, and eyes and to high blood pressure. Treatment is therefore absolutely necessary. There are different possibilities for this:
- treatment with medication
Hormone production in the thyroid gland can be inhibited with medication. This inhibition is reversible. This means that when the medication is stopped, hormone production increases again and the symptoms reappear. Therefore, the medication must be lifelong.
About a quarter of cats treated with antithyroid drugs may experience side effects such as vomiting, diarrhea, and decreased appetite. In addition, the administration of tablets is difficult for many cats, which is why this therapy method is not optimally suitable for all cats.
- Treatment Of Hyperfunction By Surgery
Surgery can also be a solution for hyperthyroidism: The diseased or tumorous thyroid tissue is surgically removed, which can prove to be complicated if it is affected on both sides. Because if too much tissue is removed, the thyroid gland can become underactive, which in turn must be treated with medication.
- Treatment by radioiodine therapy
Another option for treating hyperthyroidism in cats is radioiodine therapy or RJT for short. Iodine is an essential building block for the thyroid hormone thyroxine. In RJT, the cat is given radioactive iodine, which accumulates in the thyroid gland. The radiation emitted damages the surrounding glandular cells, which reduces the production of hormones. Side effects have not yet been observed and the success of the therapy speaks for itself: in 95% of cats, a single RJT leads to normalization of the thyroid function after two to three weeks.
However, this form of therapy also has disadvantages. Because it is very expensive and is only carried out in Germany at the University Hospital Gießen and the Animal Clinic Norderstedt, which is why you may have to put up with long journeys. In addition, the cat is hospitalized for up to ten days.
- Treatment of hyperfunction through the feed
In the case of mild forms of hyperthyroidism, therapy can also be carried out through the food. Some feed manufacturers already offer iodine-reduced feed, which is said to improve thyroid levels when fed exclusively. However, it is important that the cat does not eat anything else, which is often difficult to control with outdoor cats.
Hypothyroidism In Cats
An underactive thyroid gland (hypothyroidism) is very rare in cats. It usually occurs as a secondary condition to hyperthyroidism treatment and is short-lived.
The situation is different with congenital thyroid defects, which can also cause hypofunction and lead to severe growth disorders in young kittens. In adult cats, signs of hypothyroidism include weight gain and extreme lethargy. Since hypothyroidism rarely occurs in cats and if it is often only temporary, it only has to be treated in a few cases by administering thyroid hormones accompanied by regular blood tests.