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Low-T Labs: Interpreting Testosterone Therapy Labs : A Patient’s Quick Guide to TRT Labs.

Keywords: Total Testosterone, Free Testosterone, Lipid Panel, PSA, Hemoglobin, Hematocrit, Complete Metabolic Panel, Estradiol, Estrogen in Men.

Testosterone replacement therapy for Low-T in Colorado, Florida, Tampa, Orange Country, Los Angeles, Palm Peach, Orlando, Texas, Austin, El Paso, Houston, Austin, Dallas, Denver


Testosterone is most accurately measured in the morning, more specially before 11:00am. Testosterone is highest in morning and then declines throughout the day. Measuring serum testosterone in the morning allows a physician to observe your highest peak serum testosterone value. Serum testosterone declines throughout the day unless you engage in physical activities that will raise serum testosterone levels. A total testosterone value less than 300ng/dL is considered a reasonable cut off for men to be diagnosed with having Low-T.

When reviewing your lab form, different lab companies have different intervals for what is considered a normal testosterone value. Both Quest® and LabCorp® have different values for the normal range of testosterone for men. Often men who are in the lower quantile of the testosterone values are good candidates for testosterone replacement therapy (TRT).

Once a testosterone value less than 300ng/dL is measured a physician should also assess the patient’s symptoms. The clinical diagnosis of Low-T is a combination of both a testosterone value less than 300ng/dL and symptoms of Low-T. On occasion a patient may have a testosterone value of 400ng/dL and may still exhibit symptoms of Low-T. Providing a patient with testosterone replacement therapy despite not having a testosterone value measured to be less than 300nd/dL is per the physician’s judgement and understanding the risk and benefits of testosterone replacement therapy (TRT).

Free Testosterone

Free Testosterone measurement is not considered a standard test initially obtained on men who are being evaluated or Low-T. Free Testosterone is the biological active portion of the total testosterone that is able to exert an effect on the androgen receptor.

Total Testosterone = Free testosterone + Bound Testosterone.

A physician may desire to order a free testosterone level if a man’s total testosterone is normal yet symptoms of Low-T are present. Free testosterone provides a physician a better understanding of your total testosterone breakdown. For more information on measuring free testosterone and factors that can affect free testosterone visit the following article.

Lipid Panel

A lipid panel is a blood test that measures your cholesterol and triglycerides (fats in the blood). A lipid panel will often report the following measures:

Total Cholesterol


High Density Lipoprotein (HDL)

Low-Density Lipoprotein (LDL)

It is important for a physician to asses a lipid profile when treating a patient on testosterone, because testosterone replacement therapy can alter lipid parameters.

Total Cholesterol: an evaluation of all cholesterol levels in the blood (combines your HDL, LDL etc.). A normal Total Cholesterol level is less than 170mg/dL

Triglycerides: a type of fat found in your blood. The body converts the calories you ingest into triglyceride’s to be used as energy when needed. Triglycerides are a type of stored energy. Elevated triglycerides can accumulate in major blood vessels, hardening and thickening the walls of major arteries in the body. This can lead to stroke, heart attacks and elevated blood pressure (hypertension). Normal Triglyceride levels are less than 150mg/dL.

High Density Lipoprotein (HDL): a good type of cholesterol in your body that prevents and protects arteries and your heart. Higher is better. A value of 45mg/dL for HDL is good.

Low Density Lipoprotein (LDL): A bad type of cholesterol that builds up in arteries and can contribute to heart disease, high blood pressure and stroke risk. A good value for LDL is less than 100mgdL.

Hemoglobin and Hematocrit

Hemoglobin and Hematocrit are measurements of the total number of red blood cells and volume of red blood cells respectively. TRT can raise red blood cell volume in the body by stimulating the bodies bone marrow to produce more red blood cells. In fact, testosterone used to be a treatment for patients with anemia (low red blood cell count . Higher levels of blood volume and red blood cells can thicken the blood. This can lead to side effects of TRT. Monitoring hemoglobin and hematocrit is imperative to proper Low-T therapy and reducing side effects.

Luteinizing Hormone (LH)

LH is a hormone produced by the anterior pituitary gland and stimulates the primary production of testosterone from the testicles. Measurement of LH provides insight into whether a man’s low testosterone is due from testicular failure or from pituitary dysfunction.

Sex hormone Binding Globulin (SHBG)

Sex hormone binding globulin (SHBG) is a protein made by the liver and binds testosterone in the body. Testosterone bound to SHBG prevent testosterone from binding to the androgen receptor. Men with elevated SHBG levels can exhibit an elevated total testosterone level but still have a significant portion of their serum testosterone bound to SHBG, lending to symptoms of Low-T. Measuring SHBG helps a clinician better understand total testosterone value and tailor therapy to improve TRT response.

Complete Metabolic Panel (CMP)

A complete metabolic panel (CMP) is blood measurement of the is comprise of liver functional panel and basic electrolytes to asses potassium, renal function and sodium among others. A CMP can given insight into underlying medical conditions prior to starting TRT.


The predominate form of estrogen in men is called Estradiol (E2). Estradiol is a breakdown product of testosterone. Measuring estrogen levels in men before TRT is important to assess the degree to which a man breaks down ( aromatizes ) testosterone. Arimidex is an estrogen blocker medication is that is commonly prescribed with testosterone to keep exogenous testosterone from being broken down and maintain healthy estrogen levels. Estrogen levels are important for healthy male sex drive, erectile function and vascular health. The goal if estrogen management is to maintain estrogen in healthy range while on TRT and not to keep is consistently low. Learn more how to manage estrogen in men.

To obtain TRT from an physician at REGENX Health, Contact Us today

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