Hyperthyroidism in Cats: So Treatable if Diagnosed Early

My 3 o'clock appointment was with a new patient who had the classic signs of hyperthyroidism in cats: severe weight loss, diarrhea, increased thirst, increased urination, and an increased appetite.

Hobbs, an adorable orange cat, had been to the emergency room 2 weeks earlier and indeed had been diagnosed with cat thyroid disease. My technician informed me that Hobbs was in to see me because his owner was out of Tapazole, the most common medication a feline hyperthyroid patient is prescribed.

The cat needed a current thyroid blood level in order for me to write a prescription for Tapazole. My technician told me that Hobbs had only been on cat thyroid medication for 2 weeks because he was first diagnosed with feline thyroid disease only 2 weeks earlier.

Thinking that this would be a fairly quick routine appointment, I headed for the exam room. Hyperthyroidism in cats is such a common disease that I've seen hundreds, probably thousands, during my veterinary career.

Diagnosis of Hyperthyroidism in Cats

The diagnosis of feline hyperthyroidism is usually simple and the treatment straightforward and very successful. It's one of those diseases that we, as veterinarians, like to diagnosis in the sense that if a cat has to have something, we hope that it is cat thyroid problems because of the easy, successful treatment.

To diagnose feline thyroid disease, we rely heavily on the history, the physical exam, and the blood work.

The history of a cat with cat thyroid problems almost always resembles that which Hobbs' owner gave:

- increased thirst

- increased urination

- increased appetite

- weight loss

- There may also be a history of vomiting and/or diarrhea.

As I entered the exam room, I said hello to the client and immediately noticed her really handsome, although thin, kitty. Hobbs was as sweet as he was handsome and so easy to examine. I admired and petted him as I repeated aloud the history that my veterinary technician had given me in order to verify that I had the facts correct.

Feline Hyperthyroidism Treatment

As sometimes happens, the cat's medical history that was reported to me by the client was different than that told to my technician. Hobbs' owner told me that her cat had actually been diagnosed 2 years earlier with feline thyroid disease. Hobbs had been prescribed the appropriate medication (Tapazole) at that time, but when the cat's owner got home and tried to give it to him, she found that it was too difficult to administer pills to her cat so she gave up. Hobbs hadn't received his feline hyperthyroidism treatment at all in the two years since!

The owner reported that Hobbs now had severe weight loss and bloody diarrhea and wasn't eating at all. The emergency clinic had recently run a feline thyroid test. She gave me a copy of the results and I am not exaggerating when I tell you that it was the highest thyroid reading I have ever seen in a cat!

The veterinarians at the emergency clinic had restarted Hobbs on his feline hyperthyroidism treatment and instructed his owner to take her kitty to a local veterinarian in 2 weeks for a thyroid blood level.

As I listened to her story, I had to bite my tongue, freeze an understanding smile on my face, and breathe deeply. Understand, please, what is upsetting about this situation. I do not blame anyone in particular and if I did, it would probably be the initial veterinarian that had diagnosed the kitty 2 years ago. He should have told the client to phone him if she had ANY problem giving the cat thyroid medication, the Tapazole, to her kitty. He should have called her a few days after the veterinarian visit to see how things were going with Hobbs' treatment.

However, I find nothing is gained through blame. But what was upsetting was looking at this great cat and knowing what I knew about hyperthyroidism in cats and its terrible effects on just about every organ in the body. It made me sad, angry (at the situation), annoyed, frustrated, scared for the kitty......

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You see, while cat hyperthyroidism left untreated has serious consequences, if it is treated, the cat can be cured or even just controlled and lead a normal life and have a normal lifespan. So when I see or hear of a cat who is a known hyperthyroid cat but hasn't been treated, it's very difficult to swallow.

You wouldn't believe the number of times an owner has brought her cat in for weight loss and vomiting or diarrhea and as we obtain the blood samples I tell her, "if it has to be something, let it be hyperthyroidism". Hundreds, thousands of times I have said this. And that's because cat thyroid problems are so treatable.

Hobbs had gone 2 years without his feline hyperthyroidism treatment all because it was difficult to give him pills. You know how many cats are like that? Plenty!

How Could This Case of Hyperthyroidism in Cats Have Been Managed Differently?

There were several things that could/should have been different about this situation.

(1) The initial veterinarian could have educated the client more thoroughly on the dangers of not treating cat thyroid problems.

(2) The veterinary office should have had a system in place that reminds them when to check up on patients that have been in recently. Hobbs' mommy should have received a phone call asking how her cat was doing and how the medicating was going and to remind her he needed a thyroid recheck in 3 weeks.

(3) The owner should have called her veterinarian when she found that she couldn't get the Tapazole pills into Hobbs instead of looking at him and saying "He looks ok to me; how bad can it be if he doesn't get his medication?"

(4) The owner should have taken Hobbs back to the vet for at least a yearly check-up regardless of the cat thyroid problem. If the kitty had his annual physical, more weight loss would have been apparent and new blood levels would have been analyzed showing even higher levels of thyroid hormone.

That, perhaps, would have led to the veterinarian properly educating the client about the devastating effects of not treating hyperthyroidism in cats and led to a discussion about alternative types of medication for cat thyroid problems that might be easier to administer (liquid, ear gels). It also, hopefully would have led to a discussion about alternative feline hyperthyroidism treatments including surgical removal of the thyroid glands or radioactive iodine treatment.

The Consequences of Letting Hyperthyroidism in Cats Go Untreated

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However, none of that happened and now Hobbs was several pounds lighter and had stopped eating altogether and was having bloody diarrhea. That, of course, is what was apparent on the outside.

What the owner didn't know was that over the last 2 years, her cat's heart had been pumping much too hard in an effort to keep up with his hypermetabolic state. Hyperthyroidism in cats, over time, causes the heart muscle to thicken, resulting in a type of feline cardiomyopathy. The cat's heart progressively cannot perform as efficiently, and eventually congestive heart failure will occur.

All of which can be avoided by treating the hyperthyroidism.

Fortunately, the outcome of this case may still be a happy one. Hobbs began medication again, he started eating, and any cat heart disease he has may still be reversed. This isn't often the case with hyperthyroidism in cats after TWO years without treatment.

I shared this feline medical case about cat thyroid problems with you in the hopes that you would learn several lessons from it.

(1) Hyperthyroidism in cats is a serious disease and should never go untreated.

(2) If your vet prescribes medication for ANY condition and you get home and can't get it into your kitty, call your veterinarian for an alternative treatment.

(3) Any time your vet tells you that your kitty has any condition, ask questions. Learn everything you can about it, ask how serious it is, ask what the options are, ask what will happen under various scenarios, go back for rechecks ....in essence, take a very active role in your cat's medical care.

Your cat's life may depend on it!

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What Other Cat Lovers Have Said About Feline Hyperthyroidism and Cat Thyroid Problems

Click below to see questions or stories about hyperthyroidism in cats from other cat lovers...

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