Thyroid Replacement Therapy: Cookie is Hypothyroid (Part III)

Continued from part II

The hardest part of dealing with hypothyroidism in your dog is getting the proper diagnosis. Hypothyroidism is both over- and under-diagnosed at the same time.


Diagnosing hypothyroidism is not straight-forward.


If not tested correctly, there is a high likelihood of misdiagnosis.

The main reason why your dog might get wrongly diagnosed with poor thyroid function is when your vet tests for T4 while your dog is sick or on certain medications. Many diseases and medications cause low thyroid hormone levels in the blood while thyroid function might be perfectly fine. For example, when Cookie had pancreatitis, her thyroid hormone tanked. The only reason it appeared on that blood panel in the first place was that it was some kind of "lab special deal" at the time.

The good news is that once diagnosed, treatment is relatively simple.


There are, however, a few things to keep in mind if you want your dog's thyroid replacement therapy to work satisfactorily. These things are important and yet they seem to be widely unknown, including veterinarians.

Thyroid replacement therapy dosage


There are two things that might be a bone of contention when it comes to thyroxine (thyroid hormone replacement) dosing.

First, a correct dosage is calculated based on ideal weight. Not your dog's current weight, but what should be their ideal weight. It is quite likely that weight issues had been one of the reasons you tested thyroid function in the first place.

Cookie wasn't obese but definitely heavier than I wanted. In fact, this was one of the main reasons I insisted on testing - managing Cookie's weight was a nightmare in spite of her being very active and eating less and less. Short of starving her, I couldn't have fed her less. Yet, she wouldn't drop a pound.

In Cookie's case, the vet an I had some disagreements as to what Cookie's ideal weight should be. As a rule of thumb, it's a good idea to go by how much your dog weighed at two years of age (if that information is available and if your dog wasn't already overweight at that time.)

How often should be thyroid meds given?


When Jasmine was diagnosed with hypothyroidism, she was put on what was the correct dose for her weight. Her prescription was to be given once a day. However, in dogs, the estimated half-life is somewhere between 10 to 14 hours. Do you see a problem there?

That's why the correct way is to medicate your dog every 12 hours to keep the levels reasonably stable. I didn't know that back then and the vet, clearly, wasn't aware of that either.

Thyroid meds should not be given with food.


Unless you work with Dr. Dodds' Hemopet, chances are you, or your vet, won't know this either. Giving your dog thyroid replacement with their food reduces its bioavailability, meaning that your dog will end up under-dosed. That is because calcium interferes with its absorption.

The proper way is to give it an hour before, or three hours after a meal. Since the most common way of medicating dogs is hiding the meds in their food or treats, that can be a problem even if you don't give it with a meal. If that's what you need to do, Dr. Dodds recommends giving it with peanut butter because only trace amount of calcium is present.

This has been working well for Cookie, though we did run into consistency issues with some of the quality peanut butters out there. Eventually, we found a brand that stiffens up just right with regridgeration so it can be used to hide the pills in it. Coincidentally, it is a chunky type, which, I believe, helps with concealing the pill even better. Since it's full of chunks, the pill just feels like another one. I suspect that in smooth peanut butter the pill would stick out like a sore thumb to Cookie.

We'll be testing Cookie's response to therapy in a couple of weeks.


She has been losing weight, though, feeling and looking good so it seems that her dose is correct.


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)



Do you have a story to share?

Your story can help others, maybe even save a life!


What were the first signs you noticed? How did your dog get diagnosed? What treatment did/didn't work for you? What was your experience with your vet(s)? How did you cope with the challenges?

Email me, I'll be happy to hear from you.




Symptoms to Watch for in Your Dog now available in paperback and Kindle. Each chapter includes notes on when it is an emergency.