Readers Respond: Living with a hyperthyroid cat

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.

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 Sadly, many vets remain out of date and either start too high or increase doses too much at a time.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.

—MHK45

Hyperthyroidism

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