Veterinarians give your patients the best care for hyperthyroidism

Radioactive iodine 131 (I-131) treatment for cats with hyperthyroidism is now available for your cat at the Sydney Hyperthyroid Cat Hospital located on Sydney’s North Shore.

Radioactive Iodine (l-131) Treatment for Cats

SHCH is Located on Sydney’s North Shore

Vet Referrals welcome.
Cat Owners can book directly.

Benefits of radioactive iodine treatment

Radioactive I-131 therapy is globally recognised as the gold standard treatment for feline hyperthyroidism and is a highly effective treatment. It treats 95% of cases with a single pill.

  • ZNo daily medication
  • Z No regular blood tests
  • ZIt is a safe cure without anaesthesia
  • ZNon-invasive: Unlike surgery.
  • ZMore cost-effective in the long run

How are the patients cared for at SHCH

What is the process

Radioactive I-131 is administered via a single oral capsule. The cat is then housed at the Sydney Hyperthyroid Cat Hospital in the customised lead
lined Cat Capsula for a period of 5-7days.

What is a Cat Capulsa

The Cat Capsula is a state-of-the-art cat facility specifically designed by Gammasonics and further customised by Dr Perkins for the effective and
safe treatment of feline hyperthyroidism using radioactive iodine.

Cat Capsula has climbing shelves for the cats to explore, is fitted with a camera for constant monitoring and supervision, and of course has its own litter tray, water and food bowls which are changed and refreshed by our trained staff daily.

Dr Martine Perkins

Dr Perkins is fully licensed and trained in the medical administration of radioactive I-131.

As a senior veterinarian with advanced medical training Dr Perkins is highly qualified to identify health issues and their implications before, during and after treatment where needed and will work with your vet to make sure the best plan is put in place for your cat.

Care and Monitoring

The feliway diffuser is constantly running in our radiation ward to keep our patients settled and calm during their stay.

Constant air circulation is maintained with an inbuilt fan refreshing the capsula with climatised air to keep the temperature at a comfortable stable state.

An oxygen port is available to provide support for those patients in need.

The radiation levels are closely monitored so the cat can be released to the owner as soon as it is safe to do so.

As a general rule, the patients spend one week with us. All our support staff are professionally trained in the use of the Cat Capsula and the correct and safe handling of radiation and the affected waste.

All treatments will be personally overseen by Dr Martine Perkins.

Learn More

We are happy to tailor a customised service to suit you and your clients without the fear of us taking over your patients ongoing care in other matters.

Our priority is to treat the hyperthyroidism and send your patient back to you, their primary veterinarian, for any other future care.

How we work with veterinarians

Step 1

Contact us

Contact us via email or phone to discuss your patients case management.

Step 2

Treatment and Care

There are several options.

You can arrange for your client to drop their cat off to us or for local clinics we are also happy for your nursing staff to drop off your patient to us.

If you need a pick up from your clinic locally we may be able to assist. Don’t hesitate to contact us to see what arrangement you would prefer for your clients.

Step 3

Reporting and Feedback

Once your cat has been discharged from the SHCH facility we will email you with an update and advise your client to return your patient to you for a follow up check 8 weeks after treatment.

Frequent questions for veterinarians

How much does it cost?

The cost is $1850 assuming your referring vet has already done a total T4 level and kidney blood test (creatinine level).

We would prefer the T4 level to be done from an external laboratory as this is more sensitive and it helps us to better determine the correct radiation dose for your cat.

If your cat needs a blood test for these values or a heart evaluation then some other charges will be necessary. All this however will be communicated beforehand so you are fully aware of costs beforehand as we do not believe in nasty surprises!

Does the patient need to be off medication 2 weeks prior to treatment?

It is still our general recommendation to have a withdrawal period for antithyroid diets and methimazole /carbimazole prior to treatment of 2 weeks, HOWEVER this is not supported by the literature, and for cats with severe hyperthyroidism a 3 day withdrawal period may be safer than having an at risk cat off medications for 2 whole weeks.

Do I have to try them out on oral or transdermal antithyroid medications first to see if the kidneys can cope with treatment of the hyperthyroidism?

It is in fact a myth that they must have been on medications to assess kidney function pre-treatment. Ignoring the hyperthyroidism to save the kidneys is no longer considered logical.

If the creatinine is normal (<140umol) then a pretreatment trial is not recommended as it has now been reported that cats with post treatment azotaemia have similar survival times to cats without azotaemia as long as they are not hypothyroid. If however a cat has pre-existing chronic kidney disease (CKD) and has a creatinine of >140umol then it may be worth trialing medication mainly because it is a financial decision as to whether to treat.

If we do treat these cats with CKD then we will likely discharge them with a small thyroxine dose for 8-10 weeks post treatment (and in sometimes for life) to ensure they never suffer form clinical or subclinical hypothyroidism.

How long is the cat away from the owner?

We house them at the SHCH for a period of around 7days. After that time the cat may be discharged .

Our recommendation at discharge however is that the owner avoid the cat sleeping right next to them for prolonged periods for the following 2 weeks after discharge.

We also advise that for the following 2 weeks they wash their hand after handling their pet, particularly before eating and avoid the pet licking their face. They should avoid direct contact with soiled litter, urine or faeces and wash hand after cleaning litter trays.

If there is someone pregnant in the house then it is best to let the cat board with us for a bit longer until the radioactivity levels are even lower.

When do we reassess the TT4 to assess treatment efficacy?

We will do a courtesy call to your client one week after discharge to assess they are happy with how the cat is going at home now that it has settled back into its home routines.

Then at 8 weeks after discharge we recommend the client return to you the referring vet for a weight check, TT4 and creatinine level. Please notify us of these results. We suggest you collect enough serum at the time for a TSH level just in case we want to add this on depending on the TT4 result.

What is the success rate?

95% of cats will be cured. 5% may require a second treatment and this will be charged at $925 if a second treatment is required. A similar proportion of cats may become sub clinically or clinically hypothyroid post treatment. If this is the case we recommend supplementing with thyroxine 50 to 100mcg/day at retesting thyroid levels again in a month. Occasionally the cats require lifelong thyroxine supplementation.

Can you check the cats heart and LA: Ao ratio prior to treatment if we are concerned about its cardiac disease?

Absolutely, Dr Perkins is happy to do a heart assessment prior. She will charge the owner only $95 for this assessment. It is often our preference to add this cost into the estimate provided to the owner if you are concerned about the cats cardiac status.

We will auscultate your patients heart at the time of admission and if we have any concerns we may recommend an echocardiogram to the owner.

Can other medications be given to the cat whilst it is hospitalised with you in the radioactive iodine ward?

We are not allowed to physically handle the cat whilst in the radiation ward. We can however supply medication in the food if needed.

When should I be concerned that the liver parameters are too high and may be more than hyperthyroidism?

An ALT or ALP < 500 is likely a result of the hyperthyroidism. If levels are higher than this then other liver pathology may be a concern and although the hyperthyroidism needs treatment still it may be worth mentioning this to the owner so that they are aware that liver pathology may need to be investigated before or after treatment.