HI gecko1265.
Some good references from Red Star, however, I'll supplement these
with the following (which may be outside the scope of conventional medical
protocols):
---You definitely need the rT3 (Reverse T3) as well, as the fT3/rT3 ratio is probably the most reliable marker for low cellular thyroid function.
Look for a ratio of over 20 for healthy thyroid function. (divide Free T3 by reverse T3, but make sure you are in the same unit measurement for both.)
---Your adrenals are probably dysregulated, (my suspicion is after reading all your symptoms is Ovarian-Adrenal-Thyroid Axis Imbalance, if you wish to research this), due to ongoing biological stress, which is possibly the reason for low fT3/rT3 ratio as one of the causes is high Cortisol which is consistent with prolonged stress (internal or external)
Paradoxically low Cortisol (which is the next phase after unresolved chronic high Cortisol-could be up to years, before the body is unable to sustain the elevated Cortisol production, resulting in diminished Cortisol production!)
is another cause for a low fT3/rT3 ratio.
--rT3 originates from T4, so it might make sense to look into replacing Levothyroxine (T4) with just T3, like Cytomel, but please discuss this with your doctor. I normally favor Armour (NDT), but in this case, once verified or as a challenge, Cytomel, might work better, until the resistance gets corrected.
You can try this for a while and see how you respond to it, but it might take time to experience improvement as the body slowly removes the excess rT3.
--Another thing to rule out is vitamin D deficiency due to resistance, if your levels are not elevated after a few months of supplementation.
Your ability to recover, could also be compromised due to the following causes of Vitamin D resistance:
*General Inflammation and G/I inflammation(Very common with low thyroid sufferers) or Leaky Gut Syndrome.
* Low fat diet or issues with fat digestion also relating to not enough cholesterol for hormonal AND vitamin D synthesis ( vit D is fat soluble)
* Obesity
* certain drugs
* high cortisol
*Vitamin D Receptor (VDR) gene mutation ( genetic /autoimmune) or decreased VDR expression, common with Hypothyroid & Hashimoto's sufferers!
So if any of the aforementioned is causing Vitamin D resistance, you need increased levels of D, above and beyond normal serum levels, for optimum function.
If further testing for this is not an option at this time, then increasing your levels would be a simple and effective Vit. D resistance challenge, as long as you supplement with Vitamin K2 and Vitamin A, which protect from Vit. D toxicity.
I hope this helps and please post again and let us know, how it's going.
Note that my comments are not intended to replace medical advice.
Blessings.
Niko
The top three low/deficient states found with hypothyroidism are iron, vitamin D and vitamin B12. Vitamin B12 deficiency can cause either exaggerated or decreased reflexes. I'd recommend sublingual (under the tongue) B12.
Excerpts from Dr Mercola's article - Optimum Diagnosis and Treatment of Hypothyroidism With Free T3 and Free T4 Levels...
"Once on hormone replacement, the TSH remains useful until it goes BELOW 0.4. Then one has optimized thyroid function by the TSH yardstick; it then remains to optimize thyroid function by the yardstick of the accurate measures of the 2 thyroid hormones, the Free T4 and Free T3 levels."
"In order to optimize the hormone replacement, the Free T3 and Free T4 should be above the median but below the upper end of the laboratory normal reference range. The goal for healthy young adults would be to have numbers close to the upper part of the range, and for cardiace and/or elderly patients, the numbers should be in the middle of its range."