Feline Hyperthyroidism

Hyperthyroidism is a very common condition in cats as they get older - it means that too much Thyroid Hormone is being produced from the Thyroid gland situated in the neck.

Thyroid hormone increases that cat's metabolic rate and has far-reaching effects throughout the body. The symptoms of Hyperthyroidism that people notice at home are:

• eating and drinking more
• weight loss - often become very skinny
• Personality change
• Recurrent diarrhoea

Hunger and Weight Loss:

The cat's body uses up calories very quickly due to the faster metabolism.  All the food is burned off rapidly so that cat is constantly hungry and unable to put on weight.

Behavioural Changes:

Hyperthyroid cats often seem restless, unsettled, hyperactive or even aggressive.

Heart Disease:

Thyroid hormone causes the heart to work harder - as a result of this it grows abnormally large.  A murmur is usually heard with a stethoscope and, if left unchecked, serious and potentially fatal heart failure will develop.

Organ Damage:

All the extra protein being eaten and digested puts strain on the liver and kidneys as they must work extra hard to keep up - this can lead to kidney failure and liver disease - both will make the cat seriously ill if left untreated.  The eyes can also be affected leading to blindness.

Treatment

The good news is that hyperthyroidism is easy to diagnose (one simple blood test is usually enough) and there are several different options for treatment:

1 - Medication

Tablets can be given to control the levels of thyroid hormone.  They are usually well tolerated; side effects are not common but can occur in some cats.
Medication will need to be given daily for the rest of the cat's life.

2 - Surgery

A simple operation to remove part or all of the thyroid tissue in the neck can often cure the condition.  This can work out to be more cost-effective than life-long medication.  Your vet may advise that you begin with medication to stabilize your cat before surgery.  In some cases, a further operation is needed some time after the first.  Complications are not common but do occur from time to time.

3 - Radioactive Iodine Therapy

The thyroid glands use a lot of iodine and the rest of the body does not.  If special radioactive iodine is given to the cat, it will destroy the thyroid tissue from the inside leaving the other organs untouched.

This is a safe and effective treatment, however it can only be performed at specialist institutes (such as the Royal Veterinary College) and requires that the cat stays there, without visitors, for a few weeks.

Outlook

Once treatment has been chosen and started, check-ups and blood tests will be needed every few months.  Hyperthyroidism is a very common problem, but if treatment is started early enough it can be managed very well and your cat can live a happy and comfortable life.

If you're concerned that you cat seem to be losing weight, eating more or undergone a change in personality, please contact us and we can arrange a complete check-up including a thyroid blood test.

For more information you can go to www.hyperthyroidcat.co.uk