Curious FT3 number

February 22, 2005

I'm wondering if anyone can shed some light on my most bizarre FT3

results.

A little history: I was finally diagnosed hypo this summer, my

inital TSH was 4.27 and my FT4 was 12 (9-23.8) - this was a 3 pm

draw. I fought and founght and found an endo who agreed to treat me

after running more tests. TSH then came back as 6.37, FT4 was 13

(10 - 20) and FT3 was 4.7 (2.6 - 5.7). I felt awful at the time;

classic symptoms. The Endo put me on .25mcgs synthroid (eye rolls)

and at first it helped, but not for long. I got some generic Armour

from myrx about 2 weeks later and that helped tremendously (it was

the Time Caps stuff, not as powerful as Armour I believe). I was on

1 1/2 grains of that plus the 25mcgs of Synthroid and in November my

labs came back as TSH .59 and FT4 15 (10 - 20). She didn't test

FT3, because as we all know, you don't have to (more eye rolling).

She told me at that time that this was 'as good as it gets'. I'd

never feel better than I did then. Any more hormones and I'd be

hyper (can you tell she was only focussing on the TSH?).

Immediately following that meeting I went to see a doctor and a

biochemist at a private clinic (if you're in canada this place is

THE place to go www.thewellnesshospital.com). I also increased my

meds but had to switch to cytomel because myrx went bellu up and I

couldnt find Armour / Generic anywhere. At the clinci They did a

huge workup on me, found my serotonin, dopamine, Vit D, B12,

progesterone and estradiol were all in the toilet. I'd told them I

was self medicating along with what the endo had me on and they

prescribed for me the level I was at then - 125mcgs T4 and 7.5 mcgs

of time release bioidentical T3. I had my labs done last week and

just got the results back:

TSH .03

FT4 18 (10 - 20)

FT3 4.7 (2.6 - 5.7).

I feel great, BTW. Between the nurotransmitters, the B12 injections

and the progesterone cream I've NEVER felt this good. But I'm

curious about that damned FT3 level. It's still 4.7 - the same it

was back in September before ANY hormones whatsoever.

BTW, the doctor I just saw today was really interested in the

research I handed him about TSH suppression and osteoporosis (he

initally wanted to lower my dose, but I " educated him " as he said

and it's staying where it is - what a difference it makes finding a

doctor who listens to you!)

Anyone have any idea what's going on - do you think my FT3 will come

up now that my FT4 is higher? Or is 4.7 where my FT3 likes to be and

that's THAT? I'm not overly concerned, I feel GREAT right now - I'm

more curious than anything.

Thanks!

Nat

February 22, 2005

I have an idea why this is and it is not neccessarily a bad thing. I

will get to that later.

________________________

TSH then came back as 6.37, FT4 was 13

> (10 - 20) and FT3 was 4.7 (2.6 - 5.7). I felt awful at the time;

> classic symptoms.

__________________

Low dose thyroid therapy can make you more hypothyroid. It sure did

me. The heatlhy human thyroid makes between 220 and 37 mcg of

Synthroid equivelent a day. So, if you take 100 mcg, then your

pituitary is supposed to adjust TSH to tell your thyroid to make

another 120 to 270 mcg to get your total up to about 220 to 370 or

whatever you need. In reality it doesn't work this way. Studies have

shown that doses less than about 220 mcg have no affect on the

metabolic rate due to the pituitary working to zero out medication

and keep you the same or worse off. Low dose therapy can also overly

suppress TSH and then your thyroid does not get the message to make

enough hormone over what you are taking for you to have enough.

________________

She told me at that time that this was 'as good as it gets'. I'd

> never feel better than I did then. Any more hormones and I'd be

> hyper (can you tell she was only focussing on the TSH?).

___________________

This is the most monsterously cruel thing doctors do to patients.

May she die and go to hell and become miserable hypothyroid and go

around and be abused by doctors for eternity.

_____________________

125mcgs T4 and 7.5 mcgs

> of time release bioidentical T3.

____________________

This works out to about 155 mcg of Synthoroid. You could still

safely go up more if you felt you needed it.

>

> TSH .03

> FT4 18 (10 - 20)

> FT3 4.7 (2.6 - 5.7)

________________

Here is the reason that I think it is the same. It has to do with

what happens in primary thyroid failure. As the thyroid is less and

less able to make enough hormone, it changes the proportion of T4 to

T3 that it makes. As thyroid function declines, the thyroid makes

more and more T3 as a way to give the body more energy. And T3

requires less iodine and is easier to make for a sick thyroid.

Studies that look at declining thyroid function have found that the

thyroid compensates by making more and more T3 to the point where it

is making almost all T3 in severe hypothyroidism.

At the same time the body attempts to adapt to declining T4 levels

and increases it's conversion of the dwindling T4 to T3. It does

this in part by increasing cortisol production and there are other

changes that occur. In this way, the body is able to adapt to very

low thyroid levels and the person is often not aware they are sick

for some time. Though, when T4 gets too low, the person has no

capacity for stress and sickens easily and can't handle things.

So, often when people show up at the doctor with progressive thryoid

failure, they have T4 that is very low at the bottom of the range or

way out of it but T3 will remaind near the middle of the range. So,

in many people, the body is able to maintain fairly normal T3

levels, but because their bank account of T4 to convert in stress or

extra demands is low, they are having lots of trouble coping. They

run out of sufficient thyroid in stress, illness and extra activity.

So, the reason your T4 has not changed much has probably a lot to do

with these mechanisms that kept T3 close to normal even when you

were sick. Also, all the tests you ran were measuring thyroid in the

blood and not in the tissues. When thyroid levels decline, the body

lets some organs be deprived in order to have enough thyroid in the

blood to maintain heart function and other more essential functions.

Studies have found that blood levels of thyroid do not correlate

with how much is in tissues and organs and they can be deprived but

blood levels are normal.

Tish

Here is a note written by Dr. Derry about doses.

__________________________

The statement by C.P. Lalonde in 1948 review: " When thyroxine is

administered to a thyroidectomized or myxedematous patient, it takes

250 -350 micrograms of thyroxine to maintain a normal metabolism.

( et al, 1935, Means, 1937) "

C. P. Leblond. Iodine metabolism. Advanc Biol Med Phys 1:353-386,

1948.

It does not say but I believe they gave it intravenously because it

is so badly absorbed orally. But IV thyroxine works well.

______________________

Other researchers have found that they were unable to raise the

metabolic rate of healthy people until the thyroid doses got up to 3

to 5 grains or 220 to 370 mcg.

February 22, 2005