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Avatar universal

Is 1.6-1.8mcg/kg T4 standard?

I got diagnosed with Hashi since Apr this year and I think my Endo has been pretty "slow" in upping my T4 meds. I understand she needs to start off at 25mcg as a safety guideline and after 6 wks I was put on 50mcg T4 + 5mcg T3 daily. My FT4 and FT3 are still below the mid & upper 1/3 of range and i'm tempted to get her to just increase my meds to at least 100mcg T4 on my next visit as I'm still putting on 1kg/mth.

I've read that dosage for normal adults can run from 1.6-1.8mcg per kg body weight. If that's so, my current 107kg is seriously under-dosed. LOL

*I have 2 colleagues who are Hypo weighing around 55kg takes the same T4 dosage as me…..*
3 Responses
649848 tn?1534637300
There really is no "standard" dosage, because we're all so different in the way we metabolize thyroid hormone, etc.

What are your current thyroid levels?  You should be getting tested for Free T3 and Free T4 at approximately 6 week intervals when meds are being actively adjusted.  Please post your current levels and be sure to include reference ranges which vary lab to lab and have to come from your own report.

It takes 4-6 weeks for each new dosage increase to reach it's full potential and it's always best to increase slowly.  Jumping directly from 50 mcg to 100 mcg skips over both 75 mcg and 88 mcg, either of which may be sufficient for you.  When I was diagnosed hypo, my doctor thought my end dosage would be 100 mcg; however, I ended up stopping at 88 mcg for several years and have just, within the past week made the move to 100 mcg.  Had I been taken directly to 100 mcg, I've have been severely overdosed for several years.

649848 tn?1534637300
Forgot to ask about symptoms.  What, if any, do you have?
Avatar universal
The dosage you state is correct but is not based on your actual weight. It is the general guideline based on lean body mass/ideal body weight (IBW) which is a better indicator of replacement needs. IBW is based on sex, height, and frame size.

Not everyone needs full replacement and as Barb135 stated, we are all different and it is better to work upward slowly based on lab results than to risk overdose based solely on a general guideline that may or may not be right for you.
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649848 tn?1534637300
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Queensland, Australia
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