Why do doctors presribe synthroid over cytomel for thyroid conditions?

[chaznad]

my sisters doctor prescribes her synthroid, a t4 ,for her thyroid problem.. i did some reading on the drug and learned that t4 's job is to convert to a t3 , but theres a chance that it wont
so why dont doctors just provide her with t3 (cytomel) ,, shes been on it for 3 years and hasnt lost weight (obviously diet/training has a lot to do with this but either way i think shes wasting her time on it )

your educated opinion?

[chaznad]

bump

[magic32]

The prescription isn’t for necessarily for weight loss, though it may occur when she is rebalanced. As you expressed exercise and diet are still paramount, since many people have fully functioning thyroids yet remain obese/overweight.

Assuming the doctor knew what he/she was doing, the diagnosis (hormone and amount) is often based on type and degree of the problem.

However, if you feel she has been misdiagnosed (which is quite possible) get a second opinion.

M.

[firedso]

T4 works fine imo.

[stupidhippo]

because it is better for HRT purposes.. i havent checked but it has a longer half -life probably and by it the levels of TSH and active thyroid hormones can be kept where wanted.. now im not 100% sure about this but it would make sense..

[skipp]

t4 has a much longer half life, teh hippo is correct.

[Xtralarg]

my sisters doctor prescribes her synthroid, a t4 ,for her thyroid problem.. i did some reading on the drug and learned that t4 's job is to convert to a t3 , but theres a chance that it wont
so why dont doctors just provide her with t3 (cytomel) ,, shes been on it for 3 years and hasnt lost weight (obviously diet/training has a lot to do with this but either way i think shes wasting her time on it )

your educated opinion?

Has your sister not asked the doc to explain his reasons? If not then get her to do so and see what he says, he has a more educated opinion than most.

[03-MASTERBLASTER-11]

Wanted to bump this to see if there is an update. I am wondering the pros/cons, if any, to T4 vs. T3. Will also start a new thread.

[Merc..]

The deiodinase enzyme (t-4 is converted t-3). Certain vitamins help ensure proper deiodinase . Also during dieting ( consuming less cals) levels of deiodinase can decline.

Also please see this thread as it should help..

http://forums.steroid.com/showthread.php?t=312578

Merc.

[BuffDJ]

I don't believe that cytomel T3 is available in the states. Most T4 compounds are the hype right now for hypothyroid. It's all about the drug reps and how many of them get the info out to the docs. It's a money game not a cure game like it should be.

[Indymuscleguy]

T-3 or Cytomel is available with an RX in the US. My endo has me on a small dose @20mcg/day. My Synthroid dose is 188mcg/day.

From what I have read, Synthroid or T-4, 1/3 is converted to T-3.

I had my thyroid gland obliterated with I-131 due to Graves disease. That's why I'm on those meds. I will say that Cytomel and Synthroid have stopped the weight gain I had. I was 192 eight weeks ago and now I"m 177lbs.

So, in theory, I have 80mcg that is converted and suppliement with 40mcg

[Merc..]

T-3 or Cytomel is available with an RX in the US. My endo has me on a small dose @20mcg/day. My Synthroid dose is 188mcg/day.

From what I have read, Synthroid or T-4, 1/3 is converted to T-3.

I had my thyroid gland obliterated with I-131 due to Graves disease. That's why I'm on those meds. I will say that Cytomel and Synthroid have stopped the weight gain I had. I was 192 eight weeks ago and now I"m 177lbs.

So, in theory, I have 80mcg that is converted and suppliement with 40mcg

Sorry to hear the troble you had with Graves disease .. ( some people that are close to me have it as well)

Well anyways.

t-4 is converted to t-3 (80 % of bodys t-3 comes from begin converted )

[Indymuscleguy]

Merc,

Can I send you a PM?

[Merc..]

Merc,

Can I send you a PM?

Sure .... As long as your not asking for a source.....


Merc.

[39+1]

Synthroid has been out a lot longer and Dr are more familiar with it it also cmoes in manymore different doses and it is cheaper lots of generics. IMO

[Kratos]

Synthetic T4 was praised as being preferable to desiccated thyroid (pig thyroid contains T-1-4) because it was easier at the time to assay its contents than the contents of desiccated thyroid, and because it was believed that thyroid patients need only T4, since T4 converts to T3 in people with normally-functioning thyroids.

Synthetic T3 came on the market later, and desiccated thyroid is still in use. Studies came out saying T-4 alone works as good as any treatment so doctors continued the practice of using T-4 as first line.

Increasingly, doctors are paying more attention to T3. New studies are comming out showing the importance of T3 in people who don't respond to T4 only.

[Indymuscleguy]

So reading my posting above, my current T-4 dose and T-3 dose, with a non-functioning thyroid...is that enough to keep dropping weight? My heart-rate is up and my body temp is up, which tells me my TSH is better. (TSH was 0 Yes zero, and 8 weeks later it was 95! Four weeks ago it was 10 and I am awaiting results drawn last Friday.

I have always one who never gained weight. I have gone from 170 to 193 and back to 177 currently.

Thoughts? Suggestions?

I am on an ECA stack called ZBurn and taking 3grams of CLA in combo. My endocrinologist reccommended the CLA. It seems some like it and some don't.

Thanks!

[jaysunderstudy]

synthroid has many strengths, plus doctors also prescribe meds that are more promoted than those that arent, synthroid has a generic for it, cytomel doesn't.

[Indymuscleguy]

bump for the CLA/ECA stack as posted above...

[r1ddl3r]

T4 has a longer half life, so it doesn't have to be dosed multiple time a day. Plus, as my doc said, the body controls how much t3 needs through conversion

[dupa95]

Great stuff thank you wife going through the same thing. Doc said her deit is not even close for weight loss meds are right deit is not. He suggested 1200 to 1000 call deit for her weight loss,and ever one is differt. thanks again for the great posts.

[Indymuscleguy]

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