1. Home

Your suggestion is on its way!

An email with a link to:


was emailed to:

Thanks for sharing About.com with others!

Most Emailed Articles

Modular and Manufactured Homes

Readers Respond: Living with a hyperthyroid cat

Responses: 13


From the article: Hyperthyroidism in Cats

Hyperthyroidism is a common disease of middle-aged and senior cats. The most striking sign is weight loss despite increased (sometimes ravenous) appetite.

Once a cat is diagnosed with hyperthyroidism, there are three treatment options. What option did you choose for your cat, and why?

Please share your cat's story of hyperthyroidism - how you first noticed the problem, how it was diagnosed, and what treatment option was selected for your cat.

I asked a vet..

I put my 17 yr old cat on meds and she acted like she was dead. No cuddling or moving. I had a long talk with the vet. I asked what would happen if I didn't give her meds. He said she'd last a year or year and a half. She would not suffer but would keep losing weight. She wouldn't suffer. It would be me watching her waste away that would be painful. She's so thin but still purrs, cuddles, and even chases bugs and mice. If I even think she is suffering, I'll make the decision then. Till then I'm enjoying every moment I have left. She's sitting on me as I type. I'll miss her so.
—Guest Kittymom

Hyperthyroid 17 year old cat

My 17 year old cat was just recently diagnosed with hyperthyroidism. I am trying the medication my vet suggested and feeding her Hill's Y/D...which she does not like. Her sister, same age, is still healthy at this time but has always eaten with her sister and they spend every day, every night, every minute with each other. The problem with that....the dominant cat is the sick cat. If the sick cat doesn't eat...the other cat will not eat. It looks like...if this keeps up...one is going because I cannot allow the healthy cat to starve because she will not eat if the sick cat doesn't eat.
—Guest Abby

14 year old cat

We rescued my father in laws cat as he was too old to take care of her. She was vomiting all the time so I took her to my vet and she was diagnosed with hyperthroydism. She has bee on the transdermal gel in her ears twice a day for two years now and is doing very well. She went from 3 lbs to 7 lbs and NEVER vomits anymore.
—Guest Linda


My 15 yr old cat was diagnosed with hyperthyroidism in nov 2011. He was 12. He had weighed 22 lbs. & lost 10 lbs over months. Thank god hills science diet had just come out with prescription YD cat food. He has been maintaining. His weight of 12.9. Lbs. He enjoys the YD dry and wet food. This is working well. I would never want to have to give him medication. My sister s cat came down with hyperthyroidism & had to have medication which was do stressful cuz the cat hated it. It was very sad. Her cat lost so much weight & had to be put to sleep. So heartbreaking. Maybe if the hills YD cat food had been out at that time. Things would have been different.
—Guest Dongina


my cat Shonnie was diagnosed last year and was informed by vets about pills,cream and radiation.I know from past events about pills and my fingers and she spits them out anyway.The rest were too expensive.In light of her being 19yrs old this year I told the vet I did not want to start treatment & he understood & respected that.She also has some feline dementia which goes hand in hand so I will keep her as long as she is not in pain.I will also check her tin food for iodine .
—Guest dianne


My baby Goober has been my kid since the day that he was rushed to me at what we figure was about 3 days of age. After a long lengthy rearing he was my beautiful healthy boy till the age of about 8 years old when he started to drastically drop weight and become ill. He was diagnosed with hyperthyroidism and I was told that medication was my best route. Thankfully due to being bottle fed and a huge suck he took to pills easily and without trouble. Originally when he was first diagnosed it took the vet multiple testing to get the levels right but then he stayed within a extra half a pill either way a day. Now he is turning 16 and this last fall started with dropping weight again, my vet says that his levels are normal on his 2 pills a day. Although I have now increased his food by adding wet to his diet after 16 years without and I'm still seeing him waste away. I'm heartbroken and I don't see him make it to the fall. My heart goes out to everyone who is in these shoes. Be strong..
—Guest Tanya

Cookie is not only a cat, he is family

My 10 year old cat Cookie has been diagnosed with hyperthyroidism. We noticed a few weeks ago that he was losing weight and we noticed near his back and back legs. Cookie was also drinking water whenever he could. Besides these two noticeable changes Cookie was a normal lovable cat. We decided to bring him to the vet and they took blood from him. His results came back that he had hyperthyriodism. In any situation this is the best news because it could have been much worse. We were also unable to get a urine sample from Cookie so if anyone has done this with their cat, please give any suggestions. We give Cookie a pill (methimazole) twice daily and we notice he is looking much better. We love Cookie he is the best cat. He watches tv with us, he loves people and will go up to you no matter who you are. He has always been so lovable so I would never give up on him. I want him to live a longer life with us. We love you Cookie.
—Guest Lauren

Proper Dosing and Kidneys

Giving the proper dose of methimazole to lower the T4 into "healthy" range (about 2.0-2.5 for most cats), does not accelerate kidney disease. If the cat has entered chronic renal failure, the lowering of the T4 simply reveals the true nature of the kidney condition, which can be treated. However, an overdose of methimazole that sends a cat into a hypothryroid state can cause acute renal failure. The most current protocol (according to Plumb's Guide) is to start with 1.25mg twice a day, retest in 3 weeks, and adjust dosage carefully. Continue until T4 is stable at the desired level. Sadly, many vets remain out of date and either start too high or increase doses too much at a time. Ability to make small adjustments is a primary advantage of the transdermal gel. Clinics are now learning that CRF doesn't mean iodine is out. It requires careful treatment followed by thyroid supplementation, still better than methimazole.
—Guest Forrest D. Poston

Responding to Guest Super Cat

This is in response to Guest Super Cat's question about radioactive treatment for cats with hyperthyroidism. One of my cats, who passed away due to lymphosarcoma, actually had radioactive treatment two years prior to her death when she was diagnosed with hyperthyroidism. We were lucky to have a facility nearby who would do this. The cat needed blood tests and x-rays before she can be accepted as a prospective candidate since they would not do the treatment if the cat had other health issues. So, that was the extra expense. Then we brought her for treatment and she stayed overnight as I recall. We picked her up and isolated her in a separate room with a different litter that we can flush, wear gloves to scoop,limit interaction with her to a few minutes a day... before you know it, the week is over and I just washed and dumped the litterbox. After treatment she responded well, and then a follow up blood test. Anyway, if you can afford the high costs, I would say go for it!
—Guest Rockpainter

I131 procedure

Our cat underwent the I131 at the Feline Hyperthryoid Treatment Center in WA state. She was only there for 3 days and then got to come home. Our cat is an indoor cat so I cant answer how long she would need to stay indoor. The treatment worked wonders for our cat although she did tend towards hypo-thyroid after but not enough that she needed medication. The meds for the treatment of hyper-thyroid dont cure the disease, they just control it and they can still have effects from the disease even with the meds which is why we went to I131 because its a cure. Plus our cat was not able to tolerate the meds for this including the transdermal.
—Guest Guest-WA state

Kidney disease WITH hyperthyroidism.

Main reason for writing is to help other cat owners. My cat "chicken" was diagnosed a year ago after a urine infection. Be cautious if your cat has kidney disease. She did. The extra blood to the kidneys kept it slow, we treated her with methamazole. After a blood test, levels were still high. Increased to one tablet twice daily. She did good. But, the reduction of blood flow to kidneys accelerated the kidney disease. The last blood test showed thyroid hormone was so low vet couldn't get a reading. We decreased dosage...however, Chicken went into renal failure before 2 days of the new dose. She was sleeping alot which I attributed to old age. (14). Please do not guess, keep getting those blood tests! Pay attention to behavior, & keep close to the vet. It is a simple thing to control & is usually turns out well. But with some, treating one can enhance other problems. I saw no signs until she collapsed. It hit her fast, & had to put her down. Stay close to vet!
—Guest Chicken

My Hyperthyroid cat

My cat is 13 years old. (Sylvester) crying, losing weight drastically. Tool him to the vet where an overactive thyroid was diagnosed, after taking blood this condition was confirmed. Sylvester was prescribed tablets, unfortunately they disagreed with him, making him violently sick. He was given Beta Blockers because of the persistent miaowing maybe (senility), also heart murmur. However, if it does not improve his quality of life the he maybe put to sleep. I am going to inquire about Iodine, here's hoping.


Our cat was diagnosed in January 2011 and has since been on tablets twice a day. We have put her on wet food and I crush the tablets into this and she is eating really well. She has just been back for her two month check and her levels are still high but within normal ranges now; she has also put on weight. The dilemma now is whether to have the radio active iodine treatment as against continuing with tablets for the rest of her life. What a dilemma!! Does anyone have experience of the radioactive iodine treatment option. I believe she will have to stay in isolation for up to 7 days and then stay indoors until her faeces are clear of the iodine. Not sure how long this is likely to take. Any information would be gratefully received.
—Guest Super cat

©2015 About.com. All rights reserved.