No one wants their cat to get sick, but some diseases can be easily controlled with proper treatment. Hyperthyroidism is one such disease and is quite common in older cats. By knowing the common symptoms of this condition, it is possible to get your cat the veterinary care it needs to treat and control it before other serious problems develop.

What is hyperthyroidism?

Hyperthyroidism, the opposite of hypothyroidism, is also known as thyrotoxicosis and occurs when the thyroid gland becomes enlarged and produces extra hormones. The thyroid gland is located in the neck and produces hormones called T3 and T4, which play a role in a variety of bodily functions, including metabolism and regulation of body temperature. When a cat develops hyperthyroidism, too much T3 and T4 are produced, causing the cat to become increasingly ill over time.

Symptoms of hyperthyroidism in cats

Here are some of the most obvious symptoms of hyperthyroidism in cats:

  • Excessive hunger.
  • Weight loss
  • Increased thirst
  • Increased urination
  • Vomiting
  • Behavioural changes.
  • Unkempt coat

The classic signs of hyperthyroidism are excessive appetite along with weight loss. Some cat owners often say that their cat seems to eat anything in large quantities, without putting on weight. Hyperthyroid cats lose weight and may also begin to drink and urinate more. Other common symptoms include vomiting, matted and unkempt coat and behavioural changes such as aggression and hyperactivity.

Causes of hyperthyroidism in cats

There are two types of tumours that cause hyperthyroidism in cats. Most cases of hyperthyroidism are due to a benign tumour called an adenoma, but in rare cases, the cause is a cancerous tumour called an adenocarcinoma. Both tumours cause the thyroid gland to enlarge, but no one knows what causes each type of tumour to grow.

Diagnosis of hyperthyroidism in cats

If your cat shows symptoms of hyperthyroidism, it is important to make a visit to your veterinarian. The vet will perform a physical examination and obtain your cat’s history before recommending a blood test. Sometimes, enlarged thyroid glands can be detected during the physical examination. The blood test will look at how well your cat’s organs are functioning and measure the amount of thyroid hormone your cat’s thyroid glands are producing. If these hormone levels are high, your cat will be diagnosed with hyperthyroidism. Other tests may also be recommended to look for common complications seen with hyperthyroidism, such as high blood pressure.

Treatment of hyperthyroidism in cats

There are four ways to treat a cat that has been diagnosed with hyperthyroidism: dietary treatment, surgery, medication and radioactive iodine therapy. Each option has its pros and cons and may not be suitable for all cats, but most owners choose to treat the condition with diet or medication. Medication reduces the amount of thyroid hormones produced by the thyroid glands and the special diet restricts the amount of iodine a cat consumes. Iodine is essential for the production of thyroid hormones, so limiting iodine intake limits the production of thyroid hormones.

Radioactive iodine is often recommended as the ideal treatment option if your cat is a candidate, and destroys abnormal thyroid tissue. This procedure usually treats the disease perfectly, so no further treatment is usually necessary. Surgery can also cure the disease, but it is more invasive than the other three options, so it is not recommended as often.

Can hyperthyroidism in cats be prevented?

Because no one knows what causes a cat to develop the tumours that cause hyperthyroidism, there is no way to prevent the disease. The best thing you can do as a cat owner is to address any symptoms of hyperthyroidism as soon as you see them. In addition, prompt treatment of the disease after diagnosis will help prevent the development of other problems. Regular check-ups and blood tests for your older cat can help find a problem before it becomes serious, so your vet plays an important role in your cat’s long-term health.

Risk factors for hyperthyroidism in cats

While no specific breed of cat has a higher risk of developing hyperthyroidism than any other, any older cat has a higher risk of developing the disease.

Some studies suggest that cats that eat primarily canned foods, especially fish-based and poor quality canned foods, are at increased risk. One study showed that long-haired cats that are not purebred also have an increased risk of developing hyperthyroidism disease, while Siamese, Burmese, Persian, Abyssinian and British Shorthair cats have a lower risk compared to domestic shorthair cats.

More information is needed to continue to help cat owners and, hopefully, one day prevent hyperthyroidism in all cats. If you suspect your pet is ill, you can call us immediately on 932 460 805. We will be happy to help you and, if necessary, arrange an appointment to examine and analyse your pet’s health.