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Total, Free and Bioavaible Testosterone. FAI. Confusing Ranges

Hello. I have a hard time understanding the ranges of free and bioavaible testosterone. I’ve read that the normal ranges are:

Total 231-1010 ng/dl (8-35 nmol/l)

Bioavaible 83-257 ng/dL

Free 5-21 ng/dl

My SHBG is 54 nmol/l and total testosterone 27 nmol/l (778 ng/dl). According to this chart: Free & Bioavailable Testosterone calculator

my bioavaible testosterone is 302 ng/dl and free 12.9 ng/dl.

(Even more confusing, according to this chart Free Testosterone Calculator

my bioavaible testosterone is 299.9 ng/dl and free 12.8 ng/dl)

According to the range my bioavaible testosterone is higher than normal. I find that very hard to believe since my SHBG is way higher than normal for my age and my total testosterone is not too high.

If we convert my values with FAI (free androgen index), the ratio is calculated like this: total testosterone (nmol/l) divided by SHBG (nmol/l) and multiplying by 100. My FAI is 50. The normal FAI ranges are 30-150, below 50 is considered low for my age. Which put my in the low end.

How you feel? Have Any problems ?

Yeah I basically have all mental symptoms of hypogonadism. Beside that my prolactin is very elevated (without prolactinoma) my LH and FSH is elevated, my estradiol is elevated (I think). I have gynecomastia and sporadically lactation. I have a varicocele which I had throughout puberty, and I’ve suffered from symptoms of low-testosterone during puberty too. Here’s my first thread regarding hyperprolactinemia Help with Interpreting Lab Bloodwork Results

To keep it simple, since no prolactinoma were found on MRI and my LH and FSH is elevated, and with varicocele and testicular problems during puberty in mind, I now believe that I have primary hypogonadism which caused androgen defiency and estrogen excess during puberty, which in turn increased prolactin.

Lack of testosterone also created mental problems which have created many other problems in my life, and contributed to mental illness and stress, and stress is known to elevate prolactin even further (especially in the present of high estrogen, and this also explain why my prolactin levels and lactation get worse during stress). My ACTH and cortisol are also elevated.

With all that said, I just find the ranges of bioactive testosterone to be wrong. They’re not accurate compared with FAI, and they simply doesn’t make sense. For example I have a friend on TRT. Before TRT he’s total testosterone (TT) was 12 nmol/l (346 ng/dl) and SHBG 26, that gives him (according to issam) a bioactive testosterone of 186 ng/dl. That’s at the higher end of normal according to the range.

After TRT he’s TT is 28 nmol/l (808 ng/dl) and SHBG 24, which gives a bioactive value of 513 ng/dl, and he feel much better now. According to the range he’s now way too high. Obviously something is wrong here.

I’d wager this is your problem, or at least one of them. How elevated is “very”? Have you tried anything to lower it?

Most FT ranges are very low and I wouldn’t concern yourself with them

My prolactin was 920 mIE/L in June and 2760 mIE/L in August, range is 65-405 mIE/L. I’ve took a new sample this week and will talk with my doctor next week, depending on the lab work this time I will likely be described a dopamin agonist.

I’m not sure if this is my only problem though, or just a by product of the main problem - primary hypogonadism (combined with PTSD that trigger my stress hormones to be elevated easily and to some degree remain elevated). I’ll check my estradiol too, which I might have to adjust with an AI.

My plan is basically to start with a dopamin agonist to lower prolactin, after a few weeks I’ll do a new bloodwork to check my prolactin, estradiol, T, SHBG, LH and FSH again, if prolactin is still high I’ll talk with my doctor, if it’s low and everything else look fine then that’s great, however if it’s low but my estradiol is still high, LH and FSH still high, SHBG still high and FT still low (which I think will be the case) I’ll try to lower my estradiol with an AI (aromasin). Then I’ll make a new blood work a few weeks later on AI, if it still show signs of primary hypogonadism I’ll start TRT.

I’ve tried to lower my prolactin naturally with Ashwagandha and stuff like that, but it doesn’t work.

I know that the ranges usually are low, but this low can’t be real. Something has to be wrong here. According to the bioavaible T range above my bioavaible T is even too high to be considered normal. According to FAI it’s in the very low end for my age.

Ranges are ranges and vary by lab. Like I said I wouldn’t focus on it too much. You feel good and your other important lab markers are in the green, then great

Good plan