Radioiodine For Cats


Radioiodine Treatment for Hyperthyroid Cats

Forest Veterinary Centre are pleased to offer radioiodine treatment for hyperthyroid cats at our Radioiodine Unit, Eastwick Lodge, Harlow.

What is Hyperthyroidism?
Hyperthyroidism is the over production of thyroid hormones, and is the most common hormone problem seen in older cats in the UK. Like people, cats have two thyroid glands, one on either side of the neck. The thyroid gland can enlarge – this is known as a goitre and is usually due to a benign growth in one or both of the glands. The growth results in increased circulating thyroid hormones, which affect the rest of the body and can cause signs such as;

  • Weight loss – despite normal or increased appetite
  • Increased drinking and urination
  • Poor coat quality
  • Hyperactivity or “kitten like” behaviour
  • Vocalising and crying at night and restlessness
  • Diarrhoea and sometimes vomiting
  • A fast heart rate
  • Increased blood pressure, which can lead to blindness if not managed.

In many cats, the vet can feel an enlarged goitre. If the clinical signs and history fit, we will carry out a blood test to check the thyroid levels and if these are high, the diagnosis is confirmed. As hyperthyroidism is a disease of older cats, this may mean that they have other problems – especially kidney and heart disease – which could require additional tests.

Treatment options
The good news is that hyperthyroidism is a common and treatable condition. There are several options, some of which offer a permanent solution (radioiodine or surgery), and others that will manage the condition (medication or special food). Initially, your vet may recommend tablets to manage the thyroid levels and then a repeat blood sample to include checking that the kidney function is adequate. If the kidney function is sufficient we can then consider radioiodine. If there are kidney problems we would recommend continuing the tablet medication with regular monitoring.

Sophie with Simba our 100th Patient pre treatment

Radioactive Radioiodine
This is the treatment of choice in veterinary and human medicine but its use has been hampered by the limited number of centres that can offer the service. We are delighted that here at Forest Veterinary Centre at Eastwick Lodge Farmhouse, Harlow, we now have our own Radioiodine Treatment Centre. Radioiodine is given by a single injection under the skin while the cat is sedated. The abnormal thyroid tissue is destroyed, it does not affect the rest of the body, and offers a cure rate of approximately 92-95%. Your cat will stay at Forest Veterinary Centre for two weeks after the injection and then your cat will need to stay indoors for one more week when home. There is natural daylight in the cattery and 24-hour CCTV monitoring of the patients.

Radioiodine treatment costs £2,000 inc VAT but excluding the pre and post treatment tests. At Forest Veterinary Centre, every effort is made to reduce the risk of complications or problems while your cat is with us. Alex Shutes our Senior Vet at Harlow, and our qualified nurses, Sharon Hasty and Nicolle Ball, are supervising the Radioiodine unit. . Cats on medication require the medication to be taken in their food and cats that are difficult to handle in a safe manner may not be suitable patients. Vaccinations are required to be up to date. If these criteria are met we would then need your cat to:

    • Have a blood kidney test within one to two months of admission.
    • Stop medical or dietary hyperthyroid medication two weeks before admission.
    • Have and external Laboratory Thyroid blood test one week before admission.
    • Be starved from 8pm the day before admission to the unit.

Further advice can be found in our client information sheets regarding the radioiodine treatment and our discharge instructions.

Client Information Sheet on Feline Hyperthyroidism & Treatment Options

Client Information Sheet on Radioiodine (I131) Treatment for Hyperthyroid Cats 2021

Feline Radioiodine (I131) Treatment Referral form for Vets

Radioiodine Information for Referring Vets

Discharge Radioiodine


For further information or to refer a case please
email: [email protected]
Call: 01279 437433