Radio Active Iodine

Radioactive Iodine

Feline hyperthyroidism is one of the most common treatable diseases of elderly cats in Australia. Radioactive iodine is used to treat cats who suffer from hyperthyroidism with a one-off treatment curing 97% of cats with this disease. 

We are very proud at Queanbeyan Veterinary Hospital to have a partner clinic that offers Radioactive Iodine treatment.  We can easily and quickly refer patients to Kippax Vet Hospital for this treatment. Kippax regularly accepts referrals for the gold standard treatment of cats affected with hyperthyroidism.

At Kippax Vet, the Radioactive Iodine unit is located off their patient wards and houses one cat in a radiation protected cage with access to fresh food, water and litter. The cats are housed for anywhere between 7 to 10 days until they are safe to go home and interact with their families. After this period of hospitalisation, all clients receive written instructions on aftercare which is done at the referring vet's clinic. Kippax has the facilities to treat 2 cases each week, so cats can be referred ASAP.

If your cat suffers from an overactive thyroid, please feel free to contact Queanbeyan Veterinary Hospital about this treatment option for your pet. 

This section of our website is intended to help pet owners to better understand the condition (including its various treatment options).

Hyperthyroidism is one of the most common hormonal disorders affecting cats. It typically affects cats older than eight years of age. Affected cats frequently have the peculiar combination of eating a lot more food, while at the same time losing weight. They almost always drink a lot more as well.

If left untreated, affected cats suffer from heart disease, high blood pressure and marked weight loss. The condition is life threatening.

Fortunately a variety of excellent therapies exist from tablets to surgery.

What is hyperthyroidsm?

The thyroid glands are located on either side of the windpipe and produce a hormone called thyroxine. Thyroxine is an important chemical does a great many things in the body but essentially gives you your “get up and go”.

A cat with hyperthyroidism produces way too much of this hormone which has a knock on effect on many areas of the body:

  • Blood pressure
  • Heart rate
  • Kidneys
  • Metabolic rate

Hyperthyroid cats frequently develop high blood pressure which can cause problems for the heart and kidneys.

Heart disease is one of the biggest problems as the increased amount of thyroxine causes the heart to beat faster and increase in size. Eventually this process (called cardiomyopathy) results in heart failure.

Sustained high blood pressure damages the kidneys. Very often these animals have underlying kidney disease, which may complicate treatment.

These cats are burning energy at a phenomenal rate so become very thin.

What Symptoms Will My Cat Have?

Cats with hyperthyroidism often have a characteristic set of problems you may notice:

  • Weight loss
  • Ravenous appetite
  • Increased thirst
  • Using litter tray more frequently to pass large volumes of urine
  • Restlessness or hyperactivity
  • Vomiting or Diarrhea
  • Fast beating heart (you may feel this on the outside of the chest)

How Do We Diagnose Thyroid Disease?

Thyroid disease is diagnosed on the basis of symptoms and blood tests.

Treatment of Hyperthyroidism

Hyperthyroidism can be managed in three ways:

  1. Tablets
  2. Surgery
  3. Radioactive Iodine Therapy

1. Tablets

Tablet therapy can be useful, but you have to be able to give a pill two to three times a day for the rest of your cat’s life to be effective. Although this treatment option spreads the cost of treatment it costs a lot more to use tablets as pets require ongoing blood tests to monitor the success of therapy. Many cats will not toerate the medication as well. So from a hassle and cost perspective this is not always the best option.

2. Surgery to Remove the Affect Glands (Thyroidectomy)

Surgical removal is also possible and often effective way to treat the disease. However there are risks and complications involved in anaesthetising an elderly cat with heart disease (which is frequently the case with hyperthyroid cats).

3. Radioactive Iodine Therapy

This is the best treatment option for cats with an overactive thyroid gland. It is safe, effective in 95% of cases and has few in any side effects. It involves the giving a dose of a mildly radioactive iodine isotope to your cat. At Queanbeyan Veterinary Hospital this is given as an oral capsule. Because the thyroid gland is the only gland in the body that uses iodine the radioactive particles concentrate within the thyroid gland and the radiation emitted destroys only the overactive thyroid tissue. The rest of the body is unharmed - making it a wonderfully targeted therapy. Only a small number of facilities offer radioactive iodine treatment in Australia and cats are required to stay hospitalised at our hospital for a few days following treatment. 

What is the Long-term Outlook for my cat?

In most cases it is excellent. But the outlook for cats suffering from hyperthyroidism depends very much on the time of diagnosis and whether any other diseases are present. In many cases, if the problem is diagnosed quickly the treatment will cure the problem. The trick is to get your pet checked out by your vet as soon as you see any of the symptoms described above.


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