Has your cat been prescribed Vidalta? Find out all about the medication Vidalta for cats, including uses, side-effects, contraindications and more.
Being prescribed a new medication for your cat can be worrying, it is important you understand about the drugs to ensure you are giving correctly, as well as aware of any potential side effects.

Vidalta For Cats – What medication has my cat been given?
Trade name:
Carbimazole is the trade name of Vidalta.
What is Vidalta used for in cats?
Vidalta is one of the more common drugs used in the control of thyroid hormone levels in cats with hyperthyroidism. It is dispensed in as an oral tablet (10mg and 15mg).
Carbimazole is metabolized to the active drug methimazole, which interferes with the synthesis of thyroid hormones.
Adverse reactions of Vidalta in cats
- Vomiting, Diarrhoea and inappetence/anorexia maybe seen but are often transient
- Jaundice, cytopenias, immune- mediated diseases and dermatological changes (pruritus, alopecia and self-induced trauma) are reported but rarely seen.
- Treatment of hyperthyroidism can decrease glomerular filtration rate, thereby raising serum urea and creatinine values, and can occasionally unmask occult renal failure.
Struggling to tablet your cat?
We always recommend using pill putty to reduce stress for both you and your cat.
Vidalta contraindications
- Do not use in cats suffering from concurrent systemic diseases, such as severe primary liver disease or diabetes mellitus.
- Do not use in cats showing signs of auto-immune diseases and/or altered red or white blood cell counts, such as anaemia, neutropaenia or lymphopaenia
- Do not use in cats with platelet disorders (particularly thrombocytopaenia) or coagulopathies.
- Carbimazole/Vidalta should be discontinued before iodine-131 treatment.
- Do not use with low iodine prescription diets.
Can Vidalta tablets for cats be crushed?
Vidalta tablets should never be crushed. These tablets are formulated to be give a ‘prolonged release’ but crushing the tablets will inhibit this feature and the medication will not be uptake correctly by your cat.
If you are having trouble tableting your cat, we suggest using pill pockets or a pill giver.
Does Cat Vidalta have to be given with food?
Vidalta tablets may be given with or without food as long as this is consistent from day to day.

Does Vidalta have to be given at the same time every day?
Tablets should be administered at the same time every day to allow for a consistent release of the medication.
How long does it take for Vidalta to work?
Because of the very long half-life of the hormone, it will take a least three to four weeks for the blood levels of thyroid hormone to stabilise in your cat. However, you may notice some of the symptoms of hyperthyroidism subsiding before this time.
It may take a while to find the correct dose for your cat, however, never change the dose yourself – always allow your Vet to do this after interpreting blood results.
Are there any alternatives to Vidalta for Hyperthyroid cats?
Yes! If you feel this medication is not the correct one for your cat it is important to discuss with your Veterinary Surgeon as soon as possible – do not just stop the medication.
Alternatives include:
- Felimazole – another tablet form with the active ingredient Methimazole
- Thyronorm – an oral solution for the treatment of Hyperthyroidism in cats
- Methimazole Transdermal Gel – an skin contact cream, usually placed onto the ear
- Y/D food by Royal Canin – a low iodine complete cat food
All medication and food used in the treatment of Hyperthyroidism for cats is prescription only meaning only a Veterinary Surgeon can prescribe these for your cat.
Can I buy Vidalta tablets for my cat online?
Yes, there are many online pharmacy websites which sell Vidalta online, however, you will need to obtain a prescription from your Vet to be able to purchase this.
Ask your Vet for recommendations on which online pharmacies to use or find a well-established site with plenty of reviews. We ask you never to purchase from a website where a prescription is not required, it is likely a scam or the tablets may not be what they say they are. Think of your cat’s safety.
What are the symptoms for hyperthyroidism in cats?
The most common sign of hyperthyroidism is a cat loosing weight despite eating normally (or even more than normal!)
Clinical signs (not all may be present):
- Weight loss
- Palpable thyroid
- Cardiac abnormalities
- High blood pressure
- Agitated, stressed, or difficult to handle
- Vomiting and/or diarrhoea
- Increased drinking and urination
- Depression, weakness, dyspnea or seizures
Vidalta for cats is a commonly used Veterinary drug, and one which is also very safe. However, if you have any concerns it is always important to discuss with your Veterinary Surgeon.
