Respected Contributor
Posts: 4,622
Registered: ‎03-12-2010

I have just had my 3rd kitty diagnosed with hyperthyroidism.  In we humans, hypothyroidism is more common.


When cats get older, hyperthyroidism is pretty common.  Tragically, my first kitty with it ended up with hypertension leading to blindness from it.  I just didn't know until I finally noticed she was bumping into walls.  She lived to be 21 though.


My boy, Oliver, has recently been diagnosed.  He is about 11.  We noticed some classic signs.  His hair was coming out and he was pulling it out.  We were shocked when we brushed him.  His coat got this sticky, weird, feeling.  He looked narrower in his back haunches.  I also noticed him drinking more and it looked like he had lost some weight. We took him to the vet, and his level was on the high end of normal.  But it was much higher than the one before.


He is on felimazole twice a day now.  His vet called today to say his levels were way down, and this is where they want them.  His fur feels normal for him, he is seldom pulling at his fur, and his back haunch seems to be filling in.


Worth a routine level when older cats get a check up or you notice stuff like this.



Honored Contributor
Posts: 28,719
Registered: ‎03-12-2010

Re: Check thyroid in older cats

I had a cat that had thyroid problems (like his


He also had asthma.  I ended up having to give him steroids so he could breathe.  The Vet said there was a chance he could develop thyroid problems (which he eventually did).  I eventually kept him alive by hydrating him.  That was my late husband's cat, Fabio (Bo).

Respected Contributor
Posts: 2,646
Registered: ‎08-20-2012

Re: Check thyroid in older cats

Quite true.  When I had cats my vet would want to get bloodwork when they were 8 to 10 years old as a baseline for any problems brewing or that reared up in the future.  A year can be a long time metabolicaly in the life of a cat.  when She Did develop Hyperthyroidism She discussed the options with me.  We put her on meds and it took a few months of repeat labwork to find her optimal dosage.  Also it's IMPORTANT to do the follow up bloodwork because many times , as with my old girl,  correcting the hyperthyroidism can unmask underlaying Kidney disease.  It's not a set it and forget it condition.  She had 5 good years on meds and fluids given under the skin.  Well worth the monitoring to me. 

Trusted Contributor
Posts: 1,349
Registered: ‎07-24-2012

Re: Check thyroid in older cats

Right there with all of you  My precious lasted to 22+on the meds and at the end the fluids.  Sudden small mass found in bladder and it grew exponentially-within 3 months she passed. Made it all that way and the unexpected did her in. Bless you all for doing the fluids with the felimazole.  

Esteemed Contributor
Posts: 5,635
Registered: ‎03-19-2010

Re: Check thyroid in older cats

I had one that ended up with the hyperthyroidism diagnosis.  First, he had a stroke and they said cat's don't normally live long after that.  But, he kept going.  Then, he had another stroke.  I didn't take him in after that one since there was nothing they could do for him.  Later, he developed a psychotic episode and I found him standing in the toilet growling at me.  Knowing that something had to be wrong I took him in and that was when they found it.  They said the thyroid problem probably caused the strokes, but they didn't check him for that.  He lived on Tapezole for years after that.  Finally, one morning he woke up lame.  My husband thought he might've rolled over on him and broke his leg so I took him in.  There were no broken bones and they couldn't find anything.  I took him home and he came out of his carrier, looked around, and went back in. He lived the rest of his life in the carrier only coming out to eat and use the litter box.  When he got to where he couldn't do that I had to make the decision to have him euthanized.


I currently have an asthmatic cat.  He's on prednisolone since he refuses to have anything to do with the inhaler.  I do worry about the side effects, mainly diabetes, but it seems to be the only other option.

Super Contributor
Posts: 466
Registered: ‎08-27-2010

Re: Check thyroid in older cats

I have a 16 yr old with a slightly elevated thyroid level. He is a very mellow cat but suddenly started racing around and climbing onto tables and desks in a frenzy. He was hungry all the time and especially in the middle of the night. When they act differently,time for a vet visit. I maintain his levels with a twice daily dab of methimazole. Much easier than trying to pill him or worry about the other cats ingesting it. His last blood work showed normal levels in all categories.I always worry about their kidneys as they age. My old man is doing just great!