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A member asked:

Does normal (1.01) "thyroxine (t4) free, direct, s, " normal (0.931) "tsh, " and low (67) "triiodothyronine (t3)" = synthroid dose good? or go up/down?

A doctor has provided 1 answer

Thyroid tests: The tsh, and secondarily the ft4, are normally used to guide the dosage of levothyroxine replacement. T3 (liothyronine) is not normally followed for this. There are a number of issues, and you would be best discussing this with your doctor.

Answered 6/25/2018

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Related Questions

A member asked:

Graves and RAI 12 years ago. 125mcg synthroid (thyroxine). All levels normal. 6 years ago TSH dropped to 0 and Free T3 & T4 low normal. TSH won't increase?

A doctor has provided 1 answer

A member asked:

If my TSH and T4 are high and free thyroxine is normal...but T3 (liothyronine) uptake is low, should I take synthroid my dr prescribed?

A doctor has provided 1 answer

A member asked:

On my thyroid panel blood test, my T4. T3 (liothyronine) uptake, Free Thyroxine Index are normal. But, my TSH is too low. Whats that mean?

A doctor has provided 1 answer

A member asked:

TSH 1.160 (0.091 in 9/2022) T4 9.7, T3 uptake 21, Free T3 3.6, Free Thyroxine Index 2.0, NP wants to start on low dose Levothyroxine due to low T3 uptake, even though others levels WNL. Should I start taking it or not? 31, female, fatigue, wt gain?

2 doctors weighed in across 2 answers

A member asked:

On 25mcg synthroid, (thyroxine)TSH reduced frm 4.67 to 4.57; Free T4 1.2; T3 103.Doc increased dose to 50mcg.I am trying to conceive.Is it ok?

A doctor has provided 1 answer

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People also searched for:

Reason for: low TSH (3rd generation) of 0.011; TSH w/Free Thyroxine (FT4) Rfx= 0.015; low FreeT4 Thyroxine=0.7, & low Triiodothyronine Total T3=0.60?
Tsh=2.11/t3 uptake=30.3/free t3=3.3/thyroxine=9.2/triiodothyronine=102.4/ everything is normal. Why do I still feel extremely tired and irritable?
Can you please define normal level of T3 (liothyronine) triodothyronine, T4 thyroxine, and tsh.?
Low T3 (liothyronine) uptake (21%), Normal TSH (3.190), normal T4 (9.4), normal free thyroxine index (2.0). Also low BUN/creatine ratio (7). Is this normal?
Low T3 (liothyronine) uptake (21%), Normal TSH (3.190), normal T4 (9.4), normal free thyroxine index (2.0). Also low BUN/creatine ratio (7). Is low T3 (liothyronine) and BUN scores related? Should I be concerned?

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