Best T3 Dose for HRT?


I was on 140 mcg T3 for years but realized this was driving up my SHBG and had low libido.

Under 120 mcg I feel my hypothyroid symptoms come back. I really feel bad on 110 mcg for example. I feel best on 130 mcg but sexually it’s not great.

Here’s a comparison of my labs on 120 mcg or 130 mcg T3. Not suprinsing T3 drives up SHBG and DHT. I was getting my SHBG lower with boron from 54 to 47 but then it went up again to 58 after changing T3 to 130 mcg. T3 also raises my IGF-1 significantly (I had higher IGF-1 on 140 mcg)
There’s a great discrepency between measured FT and calculated FT maybe from boron.
I think I have more morning woods on 120 mcg than 130 mcg. Is it clear that 120 mcg is better? Lower SHBG should be my goal right? I may have a very high DHT but this is all bound to SHBG.
Maybe the fact I need an AI to be able to get an erection is that with too much T3 I aromatize too much.

Did you change your Testosterone protocol between the two labs? Dropping from 1600 to 710 is unusual.

What are your thyroid numbers? TBH, the doses you are talking about for T3 seem very high. I have done like 60 mcg a day, and I was hot and gittery.

I’d go off of your thyroid lab numbers, not your sex hormone numbers for dialing in T3.

I’m on Nebido 2 ml every 6 weeks. 1st lab was 10 days after injection and 2nd lab was after 6 weeks.

I just did a T3 test but it’s hard to see what it should on T3 only. Usually I’m 0 FT4 and high in range for FT3 at 9 in the morning before the 1st dose

SHBG and DHT above range with T and FT in range suggest I have too much T3

I don’t have high HR (60ish) or feeling too warm on 130 mcg

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Okay, this makes sense. That being said, I wouldn’t deduct much from the differences in libido / sexual performance between 120 mcg and 130 mcg when you have large differences in sex hormone differences because you are injecting every 6 weeks. This is a plot of Test U (nebido) for 12 weeks with every 6 week injection of 500 mg.

I think your solution to this is to get a more average T3 and FT3 readings (more blood work). Sounds like you are measuring at trough. I just say this because it may not be healthy to have high T3 values. Try to get an understanding of AUC (area under the curve) for T3 for you vs an adult with good functioning thyroid.

I’d also suggest that you advocate for more frequent T injections. 6 weeks is a long time even for Test U. I think once a week would have a majority of men feeling better than every 6 weeks.

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Very good advice! Thanks. Yes for every 6 weeks it’s the “best” I can get where I live. I was on every 10 weeks gor many years :laughing:

I think T variations also is key here for libido and sexual performance. That being said T3 can hijack this by raisong SHBG too much.