Thyroid Replacement Therapy Re-Check: Cookie Is Hypothyroid (Part IV)

So it's been a bit over six week since we started Cookie's therapy after she was diagnosed with hypothyroidism.

The recommended timeline to check whether the prescribed dose is optimal is six to eight weeks after starting.

To avoid any discrepancies with potential results variations between different labs, we decided to retest with Hemopet, where we did the initial testing. I was actually surprised how problem-free the adventure was--shipping a blood sample over the border.

We had our share of challenges trying to ship a tick for Lyme testing (a dead tick, submerged in a vial of alcohol and carefully sealed and protected) or trying to get Jasmine's adipose cells to Vet-Stem and processed stem cells over to here. Kudos to Fedex which seems to be the only provider able and willing to deliver such weird things.

Shipping Cookie's blood to the Hemopet lab was quick and smooth and the test results have come back and a lightning speed each time. You get results emailed to you the next business day from the time they received it.

Timing of the blood draw is important.

In dogs, thyroxine has a half-life of about 12 hours. To get usable test results, it is ideal to draw the blood four to six hours after administration of the meds. Being aware of that, I made sure I could get the appointment at the right time. Doing it too early or doing it to late after administration would not provide usable information about the accuracy of the dose.

I had some questions whether Cookie's prescribed dose wasn't too high.

Based on the retest results, it is a good dose for Cookie after all. The levels are kind of "highish" but we also tested 4 hours post administration. They specifically wanted to know the timing to take that into consideration when evaluating the results.

Either way, it was their conclusion that this dose is good for Cookie and I went with them specifically because they are the experts on thyroid.

Interesting thing of note is the remark regarding the T4/Free T4 ratio. Below a certain range this would mean that there is something else going on with Cookie's health. Either not related to thyroid at all, or thyroid issues plus something else along with it.

There are many things that can mess with the thyroid hormone levels which have nothing to do with the thyroid function. For example, when Cookie had pancreatitis, her T4 levels tanked.

There doesn't seem to be anything else wrong with Cookie, nor is anything showing on her other labs. Everything looked good.

Are there visible changes in Cookie since we started the treatment?

There was some quick overall weight loss right away. At the time of the second blood draw, weight didn't seem to have dropped further (as much as one can trust the scale) but I am seeing changes in the way Cookie's body looks--better defined waist etc. So we'll see how that goes.

Her tolerance to cold seems to have increased. One of the reasons I was suspecting poor thyroid function was the fact that her feet would get cold outside during freezing temperatures much faster than they used to.

By freezing temperatures I mean -20 degrees Celsius or less, just so there is no confusion. We already had a few days like that this year and it, again, takes much longer for Cookie's feet to get cold. Not exactly empirical data but worthy of observation.

Another interesting finding is that she seems to digest her bones better. Before I had to work really hard on offsetting the amount of bone she eats by sufficient amount of fiber; else her poops would get very dry and hard. It seems that she is now digesting the bone matter much better, needing much less fiber to keep her stools just the right consistency.

The fur on her main seems to be changing back to black color but that could just be from less exposure to the sun, since it's been mostly raining or snowing lately. Who knows. But it is changing so I figured I'd note it here.

Next retest is recommended on one year.

That doesn't mean I won't be monitoring how things seem to be working out for Cookie and wouldn't retest earlier if I had a suspicion something has changed in the status quo. For now, though, we won't be making any changes.

Related articles:
What Does the Thyroid Do?
When is Hypothyroidism not Hypothyroidism?

From The End Of A Lead Line To Casa Jasmine: Meet Cookie, Our New Adoptee
And So It Begins Again(?) Our First Health-Related Heart Attack With Cookie 
I Didn't Know I Could Fly: Why Cookie Wears A Harness Instead Of A Collar
C.E.T. Oral Hygiene Chews For Dogs CAN Be A Choking Hazzard 
Our First Health-Related Heart Attack With Cookie: The Knee Or The Foot?
Creative Solutions And An Incidental Product Review
Too Young For Pot: Cookie's Snack With A Side Of Hydrogen Peroxide  
Taming Of The Wild Beast: Cookie's Transition To Civilization  
Staying On Top Of The Ears: Cookie Is Not Impressed  
Putting The Easy Back Into Walking
Cookie's Ears Are Still Not Happy 
The Threat Of The Bulge Is Always Lurking 
Today Is Cookie's Three-Months Adoptoversary  
Cookie Meets The Electric Horse Fence And Her First Chiropractic Adjustment  
Why Examine Your Dog's Vomit? 
Why Is That Leg Still Not Happy? Cookie's Leg Keeps Getting Sore 
Cookie Too Is Insured With Trupanion
Does Being Insured Mean Being Covered? Our First Claim With Trupanion
Is Cookie's Leg Finally Getting Better?
Is Cookie Going To Be Another Medical Challenge Or Are We Looking Too Closely? 
The Project That Is Cookie: Pancreatitis Up Close And Personal  
Pancreatitis: Cookie’s Blood Work   
Another Belly Upset: Pancreatitis Again Or Not?  
Happy Birthday, Cookie 
Incontinence? Cookie's Mysterious Leaks 
Who's Training Whom? Stick And Treat 
Don't Just Stand There, Do Something? Cookie's Mysterious Bumps 
Cookie's Mysterious Bumps Update
One Vomit, No Vomit 
Happy One-Year Adoptoversary, Cookie!
Cookie's Leaks Are Back: Garden Variety Incontinence Or Not?
Cookie's Leaks Update 
Don't Panic, Don't Panic: Know What Your Job Is 
The Continuing Saga Of Cookie's Leeks: Trying Chiropractic Approach 
Cookie's Minor Eye Irritation
Regular Wellness Exam: Cookie's ALT Was Elevated 
Cookie's Plantar Paw Pad Injury 
How Far To Take It When The Dog Isn't Sick?
Cookie Has Tapeworm Infection 
Cookie's Elevated ALT: The Ultrasound and Cytology  
Cookie's ALT Update
The Importance of Observation: Cookie's Chiropractic Adjustment
Sometimes You Don't Even Know What You're Looking at: Cookie's Scary "We Have No Idea What that Was" 
Living with an Incontinent Dog 
Summer Dangers: Cookie Gets Stung by a Bald-faced Hornet 
To Breathe or Not To Breathe: Cookie's Hind Legs Transiently Fail to Work (Again)
Figuring out What Might Be Going on with Cookie's Legs: The Process 
Figuring out What Might Be Going on with Cookie's Legs: The Diagnosis 
Cookie's Iliopsoas Injury Treatment: Trazodone  
Cookie's Iliopsoas Injury Treatment: Other Medications 
Cookie's Iliopsoas Injury Treatment: Laser, Hydrotherapy, and Chiropractic 
Cookie's Recovery from Iliopsoas Injury: ToeGrips 
It Never Rains ... Cookie's New Injury 
Mixed Emotions: When What You Should Do Might Not Be What You Should Do for Your Dog 
Cookie's New Injury Update 
Cookie's Iliopsoas Injury: The Symptoms 
Cookie's Iliopsoas Injury: Battling the Zoomies 
Cookie's Muscle Injuries: What Else Is Going On?
Theory and Actual Decisions for an Actual Dog Aren't the Same Thing: Cookie's Knee Injury
Does Your Vet Listen to You? Cookie's Post-Sedation Complications
Would I Ever Treat a Symptom Directly? 
Platelet-Rich Plasma (PRP) Treatment for Cookie's Bad Knee(s)
Platelet-Rich Plasma (PRP) for Cookie's Bad Cruciate Update 
Injury or Surgery Recovery: Mishaps versus Setbacks 
See Something, Do Something: Cookie's Lumpectomy 
Cookie's Lumpectomy Update 
Using Pressure Pads to Evaluate Lameness in Dogs: My Observations
Cookie's Musculoskeletal Challenges: What Supplements Am I Using?
Cookie's Musculoskeletal Challenges: Restricted Activity and Weight Management
Cookie's PRP Treatment for Partial Cruciate Tear: Update
Has Your Dog's Physical Therapist Taken Dog Training Classes? 
Cookie's PRP Treatment for Partial Cruciate Tear Update and Considering the Future
Cookie's PRP Treatment for Partial Cruciate (CCL/ACL) Tear and Leg Circumference
Cookie's Wellness Exam
Ticked Off at the Tick Situation: What Do You Use for Tick Prevention?
Ticked Off at the Tick Situation: The Verdict Is In (for Now)
Cookie's Annual Heartworm and Tick-Borne Diseases Test
One Yelp, No Yelp. But Two?
One Yelp, No Yelp - Update
Cookie's Rabies Booster
Is Your Dog Struggling with Weight in spite of Diet and Exercise? Cookie Is Hypothyroid (Part I)
What Does the Thyroid Do? Cookie is Hypothyroid (Part II)
Thyroid Replacement Therapy: Cookie is Hypothyroid (Part III)
Platelet-Rich Plasma Treatment (PRP) for Partial Cranial Cruciate Ligament (CCL) Tears: Would I Do It Again?

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  1. I'm so glad that Cookie is doing well and you've discovered what works. Hypothyroid can bring a host of problems if left untreated, but it sounds like she's doing well. Now she can enjoy the beautiful, snowy weather properly.

    1. Yes, it sure can; been there before. That's why I insisted to test it properly since in local lab the results weren't conclusive. So went with Hemopet this time.

  2. Cookie is such a beautiful dog! I was a little confused about you deciding where to send the blood sample for testing. Is that not something your vet does? Sorry if you answered this already in a previous post I missed. I haven't had a dog with a thyroid problem but I did have a cat with a terrible case it was virtually impossible to get her dose right. Her numbers would go up and down like a yo yo. One night I was so scared I called the emergency hospital for advice. She had regular blood tests but she was such a challenge to treat. It was quite a long time ago but I think what first alerted me to a problem was weight loss. I do hope Cookie stays well.

    1. She absolutely is. Definitely a worthy heiress to Jasmine's legacy.

      Some vets test in-house, which normally includes T4 only but that's completely useless.

      Local labs, such as Idexx do run a panel but their normal range is too broad and totally generic, as well as one has to insist to test all values that are needed for true evaluation.

      Hemopet specializes in this, actually has a patented method for testing. As well as they know what to test, how to assign normal range based on breed, sex etc, and how to interpret the values.

      Your cat is hypothyroid? Cats usually have the opposite issue - hyperthyroidism. As well as weight loss would be indicative of that. What symptoms are scaring you? What are they treating it with?

  3. Thanks for teaching me so much when it comes to symptoms with our dogs as although I watch Layla like a hawk it is always good to read and learn more

  4. I'm glad the treatment seems to be helping. I hope she continues to improve!

  5. I had no idea that dogs could be hypothyroid just like people! So interesting. Thank you for sharing, I learned a lot!

  6. Happy to hear Cookie is improving. I had no idea you'd have so much trouble shipping the items you needed tested. Glad you found someone who would ship.

  7. I'm happy to hear that you're starting to see some positive changes in Cookie. Hope the treatment continues to work well for you guys. :)

  8. I'm glad to know that Cookie's thyroid medication seems to be working for her. I know it is obvious to you, but truthfully, I would have just assumed the same lab would be doing the retest, and not even given it a second thought. I will keep this in mind for the future.


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