Is free testosterone the main variable that matters in testosterone replacement?

[Cameron58]

My dumbass doctor has his knickers in a twist because of my testosterone levels. I was tested today, exactly half way though the week after the last shot of test cyprionate, 100mg. My total is 937ng/dl with the "normal" range being 193-740.

My free T measurement is 161pg/ml with the "normal" range being 32-168. Percent free is 1.7 with a "normal" range being 1.1-2.5.

So, that seems fine to me because the important number is the free T measurement, and that is in the normal range. My doctor is convinced that the amount I'm injecting must be cut because of the total T measurement.. I think he's full of s**t.

First, am I right or wrong. Second, if I'm right can anyone direct me to a source of reference information that verifies this, so I can give it to my doctor? I don't mean articles written by knowledgeable people. I mean rigorous, peer reviewed studies done by real live scientists that will give iron clad proof that the important measurement is the free T, not the total T? I need something so indisputable that even my stubborn idiot doctor can't disagree with it.

Thanks.

 

[Gene Devine]

Hi Cameron - You are correct in your assessment of Total versus Free Serum levels:

From our good Dr. John Crisler who I believe is one of our greatest minds in TRT for men:

TOTAL TESTOSTERONE
This is the assay your patients will most focus on, as will clinicians unpracticed in the art. Physicians who do not understand sex hormones will deny patients the testosterone supplementation they want--and need!--when Total T is at low-normal levels. Total T is important for titration of dosing, but its relevance is reduced in older men, by virtue of their increased serum concentrations of SHBG (and therefore lowered Bioavailable Testosterone), in favor of:


BIOAVAILABLE TESTOSTERONE
Where we get the “bang” for the hormonal buck, so to speak. This is the actual amount the body has available for use, as the concentration of hormone available within the capillary beds before the androgen receptor approximates the sum of the Free Testosterone plus that which is loosely bound to other carrier proteins in the blood, primarily albumin. If Bio T is not readily available, Free T may be a second choice substitute, as Bio T and Free T serum concentrations are usually well correlated. Bioavailable Testosterone is the gold standard for serum androgen evaluation.

See attachment and print it out for your Doctor to read.

View attachment TRT (4).pdf

 

[Vettester Chris]

Cameron, just curious, who's lab reference range is that? It sure doesn't resemble Labcorp or others we have seen.

Good information posted by Gene, with regards to Dr. Crisler.

 

[Cameron58]

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[TD="class: rz_i"][/TD]

[TD="class: rz_n"]Collection Information[/TD]

[TD="class: rz_q"][/TD] [TD="class: rz_r"]Specimen#[/TD] [TD="class: rz_r"]Collection Date[/TD] [TD="class: rz_r"]Collection Time[/TD] [TD="class: rz_r"]Collected By[/TD] [TD="class: rz_r"]Specimen Source[/TD] [TD="class: rz_r"]Specimen Description[/TD] [TD="class: rz_r"]Update Desc[/TD]

[TD="class: rz_s"][/TD] [TD="class: rz_j"]14U-286C1453[/TD] [TD="class: rz_j"]Oct 13, 2014[/TD] [TD="class: rz_j"] 4:21 PM[/TD] [TD="class: rz_j"][00700328][/TD] [TD="class: rz_j"][/TD] [TD="class: rz_t"][/TD] [TD="class: rz_j"][/TD]

[TD="class: rz_i"][/TD]

[TD="class: rz_n"]Component Results[/TD]

[TD="class: rz_q"][/TD] [TD="class: rz_r"]Component[/TD] [TD="class: rz_r"]Value[/TD] [TD="class: rz_r"]Range & Units[/TD] [TD="class: rz_r"]Status[/TD]

[TD="class: rz_s"][/TD] [TD="class: rz_u"]Total Testosterone[/TD] [TD="class: rz_w"]937 (H)[/TD] [TD="class: rz_x"]193-740 ng/dL[/TD] [TD="class: rz_x"]Final[/TD]

[TD="class: rz_s"][/TD] [TD="class: rz_z, colspan: 4"]New reference range instituted 3/3/2011. Assay is not recommended for girls less than 8 years old due to the low concentrations of testosterone in this population. Adult Males: 19-49 years old -- 249-836 ng/dL 50 years and older -- 193-740 ng/dL Adult females: 19-49 years old -- 8-48 ng/dL 50 years and older -- 2-41 ng/dL Boys <1 month -- 75-400 ng/dL 1-5 months -- 14-363 ng/dL 6-24 months -- Less than 37 ng/dL 2-5 years -- Less than 19 ng/dL 6-9 years -- Less than 13 ng/dL 10-11 years -- 3-237 ng/dL 12-13 years -- 29-432 ng/dL 14-15 years -- 40-778 ng/dL 16-18 years -- 238-1048 ng/dL Tanner stage 1 -- Less than 15 ng/dL Tanner stage 2 -- 3-432 ng/dL Tanner stage 3 -- 65-778 ng/dL Tanner stage 4 -- 180-763 ng/dL Tanner stage 5 -- 188-882 ng/dL Girls Up to 30 days -- 20-64 ng/dL 1-5 months -- Less than 20 ng/dL 6-24 months -- Less than 9 ng/dL 2-3 years -- Less than 20 ng/dL 4-5 years -- Less than 30 ng/dL 6-7 years -- Less than 13 ng/dL 8-9 years -- 1-8 ng/dL 10-11 years -- 3-32 ng/dL 12-13 years -- 3-50 ng/dL 14-15 years -- 6-52 ng/dL 16-18 years -- 9-58 ng/dL Tanner stage I -- Less than 17 ng/dL Tanner stage II -- Less than 40 ng/dL Tanner stage III -- 5-63 ng/dL Tanner stage IV-V -- 6-58 ng/dL[/TD]

[TD="class: rz_s"][/TD] [TD="class: rz_10"]SHBG (Sex Hormone Binding Globulin)[/TD] [TD="class: rz_11"]37[/TD] [TD="class: rz_11"]10-80 nmol/L[/TD] [TD="class: rz_11"]Final[/TD]

[TD="class: rz_s"][/TD] [TD="class: rz_z, colspan: 4"]Males: 10-80 nmol/L Females, non-pregnant: 20-130 nmol/L Reference ranges not well established for pregnancy.[/TD]

[TD="class: rz_s"][/TD] [TD="class: rz_10"]Free Testosterone[/TD] [TD="class: rz_11"]161[/TD] [TD="class: rz_11"]32-168 pg/mL[/TD] [TD="class: rz_11"]Final[/TD]

[TD="class: rz_s"][/TD] [TD="class: rz_z, colspan: 4"]Reference Range: Males 0-9 years -- Less than 1 pg/mL 10-11 years -- Less than 4 pg/mL 12-13 years -- Less than 68 pg/mL 14-15 years -- 2-95 pg/mL 16-17 years -- 26-119 pg/mL 18 years and older -- 32-168 pg/mL Tanner stage I -- Less than 3 pg/mL Tanner stage II -- Less than 15 pg/mL Tanner stage III -- Less than 68 pg/mL Tanner stage IV -- 24-117 pg/mL Tanner stage V -- 28-165 pg/mL Females 0-9 years -- Less than 1 pg/mL 10-11 years -- Less than 3 pg/mL 12-13 years -- Less than 5 pg/mL 14-15 years -- Less than 6 pg/mL 16-17 years -- Less than 7 pg/mL 18-30 years -- 1-5 pg/mL 31-40 years -- 1-6 pg/mL 41-50 years -- 1-4 pg/mL 51 years and older -- Less than 3 pg/mL Tanner stage I -- 1-12 pg/mL Tanner stage II -- 4-28 pg/mL Tanner stage III -- 7-44 pg/mL Tanner stage IV-V -- 8-43 pg/mL[/TD]

[TD="class: rz_s"][/TD] [TD="class: rz_10"]% Free Testosterone[/TD] [TD="class: rz_11"]1.7[/TD] [TD="class: rz_11"]1.1-2.5 %[/TD] [TD="class: rz_11"]Final[/TD]

[TD="class: rz_i"][/TD]

Reviewed by List

Cameron, just curious, who's lab reference range is that? It sure doesn't resemble Labcorp or others we have seen.

Good information posted by Gene, with regards to Dr. Crisler.

 

[Cameron58]

This is very helpful info from Dr. Crisler,, and I'm sure my doctor will totally discount it as having been written by a doctor who makes his living peddling TRT to men who may not need it. That's not my opinion of the information. . My doctor will only pay attention to research studies done at or published by sufficiently prestigious academic institutions or other organizations. I'm trying to find another doctor, but I'm dealing with the challenge of finding one who prescribes TRT, accepts Medicare, and does not have his head stuck up his ass.

 

[Nelson Vergel]

Cameron

Your total T is not excessive provided that your hematocrit is in control.

No, there really are too few references on free testosterone being the main monitoring variable since its calculation is variable depending on methods and labs. However, there are a few studies that have linked free testosterone in particular with erectile function and cognitive capacity.

Normal testosterone ranges from 350-1100 ng/dL. Yours is within range.

Here are a few studies that looked at free testosterone:

http://press.endocrine.org/doi/abs/10.1210/jc.2002-020419

http://www.neurology.org/content/62/2/188.short

http://www.jurology.com/article/S0022-5347(05)67812-3/abstract

http://onlinelibrary.wiley.com/doi/...nticated=false&deniedAccessCustomisedMessage=

http://onlinelibrary.wiley.com/doi/10.1359/jbmr.060110/full

http://link.springer.com/article/10.1007/BF01541548

 

[Nelson Vergel]

Cameron58

Where do you live?