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Dr. B.
Dr. B., Cat Veterinarian
Category: Cat
Satisfied Customers: 22448
Experience:  I am a small animal veterinarian with a special interest in cats and am happy to discuss any questions you have.
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My cat is 20 yrs old and has ckd and hyperthyroidism. He is

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My cat is 20 yrs old and has ckd and hyperthyroidism. He is on a special renal diet.The vet has suggested him going on Vidalta but it could make the kidney prob worse.What should I do carry on with renal diet or consider Vidalta .Not happy with latter as you cant crush them and she says it costs £25/month the tablets.

Hello & welcome, I am Dr. B, a licensed veterinarian and I would like to help you with your wee one today.


First, I must say that treating the hyperthyroidism will not make the kidney worse. Instead, the dilemma we face is that hyperthyroidism will mask the severity of the current level of kidney disease a cat may have. This happens because as I am sure you are aware, hyperthyroidism causes increased heart rate and blood pressure. This means that before the thyroid treatments, your cat's kidneys would be getting blood pumped through them twice what is normal. And if kidneys are getting old, struggling to function, and filter as they should, then more opportunity to filter the blood will allow them to do their job better even though they are compromised. And when we then treat the thyroid, thus leading to a normalization of heart rate and blood pressure, the fact that the kidneys are struggling can then become apparent. So, treatment of the thyroid doesn't worsen the kidneys, it just takes away that extra blood flow the kidneys were getting and therefore make the kidney's actual severity more clear and more apparent.


Now when we consider that benefit his thyroid disease had on supporting his kidneys, I know it will make people wonder why we'd correct a disease that was supporting the kidneys. The reason is because with these two diseases we find ourselves in a catch-22. Because even thought the kidneys had better filtration flow with this disease, hyperthyroidism has a lot of negative effects. As I am sure your vet mentioned, uncontrolled hyperthyroidism is like a cat being on 'fast-forward'. And this takes its toll, leading to weight loss, wasting, heart disease, and even the risk of throwing clots (that can induce painful paralysis in the cat). Therefore, we do treat and if we have kidney issues then we need to support that as well.


In regards XXXXX XXXXX so, treating with Vidalta and the renal diet (+/- additional kidney treatments if they did start to struggle and he started suffering with signs of kidney disease) would be ideal. That said, with tableting and cost being an issue, I would make the suggestion that you could consider the new hyperthyroid diet called Hill's Y/D. (More info-- HERE.) As long as he will eat this diet, it is a good means of treating his thyroid disease (it does so by limiting his iodine access which limits how much thyroid hormone he can make) without having to tablet him. Furthermore, as so many thyroid kitties have kidney troubles too, the diet is designed to be lower in those components (protein, sodium, phosphors) just as his current diet. So, it will address two birds with one stone and avoid you having to tablet him.


Overall, if your lad has both kidney troubles and hyperthyroidism, they both really need to be addressed for his continual health. That said, if you are financially limited (though already purchasing a special diet) and he isn't keen on tablets, then I would suggest that Y/D may be a good option for your lad. So, do have a peek at the link above and chat with your vet about this diet option for him.


I hope this information is helpful.

If you need any additional information, do not hesitate to ask!

All the best,

Dr. B.


If you have any other questions, please ask me – I’ll be happy to respond. Please remember to rate my service once you have all the information you need. Thank you and hope to see you again soon! : )




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