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Feline Radioiodine

It’s a life-threatening condition, but thankfully it’s treatable in all cases and curable in the majority of cases.


Radioiodine treatment for cats

Did you know that an overactive thyroid gland (hyperthyroidism) is a serious problem prevalent in cats over 10 years of age? Common signs of hyperthyroidism include vomiting, an increased appetite, changes in behaviour and weight loss. It can also bring about serious secondary complications like heart disease. It’s a life-threatening condition, but thankfully it’s treatable in all cases and curable in the majority of cases.

There are several therapies for the management of hyperthyroidism but radioiodine treatment is considered the gold standard. Not only is it a highly effective treatment, but it has few, if any, side effects and is administered with a single oral capsule. It’s the same treatment used for humans suffering hyperthyroidism.

SASH Radioiodine treatment for cats

What Is Involved In The Radioiodine Treatment?

Pre-treatment consultations: Consultations for assessing cats are currently available on Tuesday 10am and 11am. If you are unable to bring your cat in at that time, please discuss this with our client services team who will contact the vet and come up with a suitable arrangement.

Cats should stop any hyperthyroid medication 2 weeks before their appointment. They do not need to fast for this procedure and all other medications may be continued as normal. Please discuss with your vet whether it is safe to stop the hyperthyroid medication, in some cases this will be discussed with the vet at SASH in order to make the visit as safe as possible.

Giving the treatment (day 1): Your cat and its medical history will be assessed at the time of the consultation to determine if it is a suitable candidate for radioiodine treatment and the radioactive iodine dose will be determined. The treatment is a capsule that is given orally, typically on Wednesday or Thursday.

We aim to give the safest, lowest, effective dose to each cat. Hospitalisation (day 2): Cats are closely monitored in our cat only hospital ward by a dedicated feline nurse and supervised by their veterinarian for any emerging problems that may affect their radioactive iodine treatment. Hospitalisation (days 3-7): After treatment, patients are housed in our radioiodine ward and are monitored each day to ensure their radioactive emissions have dropped to a suitable level. Due to strict safety regulations, you won’t be permitted to visit your cat for the duration of hospitalisation.

For your safety, cats are hospitalised for a minimum of 5 days and until their radiation levels are below a safe level. This usually takes between 5 and 7 days. Most cats are discharged the Tuesday after treatment.

Follow up: We recommend follow up blood tests between 6 and 12 weeks after treatment to check kidney function and thyroid hormone concentrations. These blood tests can be performed at your local veterinary clinic. If these results are emailed to SASH, our specialists will collaborate with your local veterinarian to provide any necessary follow up.

SASH is accredited by the International Society of Feline Medicine as a Gold Standard Cat Friendly Clinic with the experience and staff expertise to handle even very anxious cats. If you are worried that your cat may have hyperthyroidism, please see your local vet to have them checked. If your cat has hyperthyroidism, ask your vet about radioactive iodine treatment or contact our team by clicking the button below.

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Our Feline Radioiodine Team

Specialist in Internal Medicine
Specialist in Internal Medicine