Hi Doc, My name is Rod and more importantly my puddy's name is Missc and we live in Melbourne Australia. Missc is almost 13 with chronic arthritis and I have been giving her meloxicam with wonderful results. I am now treating her for hyperthyroidism with a 'natural' product called Thyroid Support Gold from Petwellbeing.com. I did not want to go down the path of drugging puddy as best I could so its worth a try. It’s only been a few days and will have another bloodwork done in 2 months. Her T4 levels are 114 nmol/L but other than that she shows no physical signs of hyperthyroidism. Anyway, this email refers to bloodwork done a few days ago compared to 2 months ago. I noticed her creatinine levels doubled from 75 umol/L to 148 umol/L. The vet did not mention anything about this when I questioned the kidney function as a concern about the meloxicam. He just said the kidneys were fine. I disagree. The vet has tried twice to get a urine sample without success. Can you shed any light on the subject? Missc has been on meloxicam solidly for 15 days now with the odd 3 day course for the past year.

Hi Rod and Missc!

Im writing this while drinking Beau’s lager. Apologies for any spelling mistakes. Long day! First off, good for you to being open to options for Missc. Not everyone would be open to trying the alternatives you describe for hyperthyroidism - and whether they work or not, what it says is that instead of having a dismissive mindset, you have a curious one. It’s a successful way of thinking when it comes to learning what works with a cat - so good on ya! I’ll be talking about that more this year on the blog but I digress...

If you can, retest the thyroid and creatinine sooner. In a month if it’s manageable. Here is why:

You chose an alternative, now test it. Retest the t4 to see if it’s working, or if you have to go to a traditional solution. I know how you feel. I didn’t want to use drugs on Zack either (see this post)...then life happens and you gotta, you know? When we have to use medications, it’s like we enter a new phase of life and things change...and we don’t necessarily want to.
Thyrotoxicosis. It’s happening right now in it’s early stages in Missc’s body. She might not be showing signs of hyperthyroidism, but unchecked thyroid levels hammer the heart and other organs. Sometimes those organs really don’t want to be hammered (i'm looking at you heart and kidneys)! There is recent research that suggest that hyperthyroidism initiates or contributes to CKD (chronic kidney disease), which you might detect as elevated creatinine in the blood. So with a thyroid level of over a hundred (pretty high), I'm pointing my finger at the thyroid..but...
Metacam. I use metacam on all sorts of cats with all sorts of issues. I don’t run into problems. There was a comment on the blog a while ago suggesting I was “lucky” to not have issues with metacam in cats. It ain't luck. Well maybe 1% luck. The rest of it is being really choosy in who gets in and how it’s administered. It can be used for cat’s with defined, stable CKD. If I have any cat with uncontrolled thyroid (which masks their true kidney situation), along with a rise of creatinine, Im staying away from metacam or any NSAID drug and going for an alternative until it’s all sorted out. Because I can't say with a good degree of confidence that I have stable kidneys in that kitty.

Definitely need the urine sample too. Third time’s a charm, right? Elevated creatinine does not a CKD cat make. It’s elevated creatinine along with loss of urine concentrating ability (so you really need the pee sample - to look for mild infection and the urine specific gravity - a fancy word for concentration). Some cat’s are CKD with normal creatinine, but the concentration of their pee is already waning. Plenty of reasons to have elevated creatinine that are different than CKD. But you are right to be concerned about it. I would be. I have some cat’s who stay with me 12 hours in the hospita and frownl...because they won’t give up the pee until it’s the last second of the last hour that they are their with me. It’s a cat thing, right?

Finally Rod, you will read a lot on the internet that treating hyperthyroid will make CKD worse. It doesn't. It unmasks what is already there. That is a huge distinction. If you are hyperthyroid, you are supplying your kidneys with about 25% more blood. A turbulent river of oxygen and nutrients for the kidney. Sort of sounds ok, right? When you cut the excessive flow of blood by treating them for hyperthyroid, a diseased kidney will show its true colours. But you need to know these colours - because yes, it’s a problem, but also, it’s an opportunity. To not cut the lifespan of those kidneys that were just ticking away unchecked. And we now know that the extra 25% of bloodflow and the benefit it brings does not outweigh the ruinous effects of thyrotoxicosis and the kidney damage it may cause. And because you are curious, and not dismissive, im pretty sure you are going to make some great choices to preserve those kidneys.

Best wishes,

Dr. Kris