Geriatric Blood Test-Low Thyroid?

[Guest chestersmom]

My 8 yr old greyhound recently had a "geriatric blood test" (two days ago) and the vet stated that all his numbers were great except that he had low thyroid levels. He wants to put he on meds. My pup is a very lively dog, good weight, happy, plays all the time- no real symptoms of low thyroid. I feel like my doc is rushing into putting him on meds. I haven't had the opportunity to call the vet for the actual numbers. What should I ask for to determine true low thyroid levels. I am aware that greyhounds have lower thyroid levels than other dogs but feel so rushed into this. If I have to put my pup on meds., which ones should I inquire about? Are they expensive? Please help.

[Batmom]

Don't start meds. The T4 thyroid measurement that is on a chemistry panel can rule out low thyroid but can't rule it in -- it isn't very useful for diagnosis.

 

If your dog had symptoms, you'd want to do a full thyroid panel that includes fT4ed (measure free T4 by equilibrium dialysis) and TSH (thyroid stimulating hormone) such as MSU's premium panel (20011 on this form http://www.dcpah.msu...DM.FORM.007.pdf ; also check the "interpretation by veterinary endocrinologist" box).

 

Since your dog doesn't have symptoms, I'd just ignore the vet's recommendation at this time. Many vets are unaware that greyhounds can have T4's that are quite a bit lower than other breeds. And, oddly, many vets seem to be unaware that T4 naturally fluctuates a lot from hour to hour, day to day, etc.

Edited January 9, 2012 by Batmom

[KF_in_Georgia]

Also, to let you know: thyroid meds are not expensive. I've been getting Soloxine for about 15 cents a pill, and Sam was taking two pills a day. (Soloxine is the brand name for a version of thyroxine, and most experts on thyroid issues in dogs will recommend Soloxine over the generic; the price difference between the two is negligible.) If your dog is hypothyroid, you'll need to retest the thyroid once a year--and that's not outrageously expensive either. Also, the dosage that dogs need is way bigger than what people would take, so you won't be able to get the prescription filled at your local drug store. There are several places online that are inexpensive; also, if it's necessary, you can ask if your vet will match the online price.

 

Batmom is right that your symptom-less dog probably doesn't need the meds at this point. I just wanted you to know that price won't be a big deal if he should wind up needing the meds sometime down the road.

Edited January 10, 2012 by KF_in_Georgia

[Guest chestersmom]

Thank you all so much for the quick reply's. The test on the vet's invoice reads, "1 Super Chem/CBC/T4/Free T4". I'm new to this so I'm not sure if this the correct type of test.

[Batmom]

It's a screening test is all. If it's low and the dog has symptoms indicative of a thyroid problem, then you'd get more specialized testing. If it's low and the dog has no such symptoms, you wouldn't worry about it. For a greyhound, "low" is a lot lower than it is for other breeds, down to zero per some sources (because the test isn't very sensitive and the amounts being measured are tiny).

 

You wouldn't treat based on that one test.

[GeorgeofNE]

I agree; don't start thyroid meds. Your dog has no symptoms of a thyroid problem. Dr. Couto believes it's the single most over diagnosed conditions in Greyhounds.

 

If you really feel compelled to spend the money (and on an asymptomatic dog, I wouldn't), get that full thyroid panel recommended above.

 

I had a dog (not a Greyhound) with a bum thyroid. It was extremely obvious something was wrong. As soon as he got on the proper Soloxine dosage, he was 100% fine again!

[Guest chestersmom]

thanks again for all your help. What a wonderful site.

[kudzu]

I would not start treatment at this point even if my vet pushed. And I cannot imagine treating an asymptomatic dog though sometimes people may not recognize some symptoms so I'm reserving that option. As other say, you need a much more complete thyroid panel run. Personally I'd choose Mich State or Dr Dodds at Hemopet. Idexx sends the larger panels (at least the important bits) out to Mich St & my vets use Idexx so that's easy for me.

 

Unlike others though I would suggest that you do the thyroid panel now if you can afford it. Down the road if you have to cross this bridge again at a time when your dog is showing symptoms you will have this labwork to compare to. It may not be the make or break in diagnosis but it sure could help. My girl only started treatment when she was 1) symptomatic, 2) had repeated testing indicative of, or at least suspicious of, lowering thyroid function, 3) explored avenues of differential diagnosis.