Testosterone Blood Test in Houston: What to Expect

What a testosterone test measures

Most testosterone in your blood is bound to proteins: sex hormone-binding globulin (SHBG) and albumin. A small fraction is "free." According to MedlinePlus, tests can measure:

• Total testosterone: bound plus free; the standard first test
• Free testosterone: the unbound portion, useful when SHBG is abnormal or total testosterone is borderline
• Bioavailable testosterone: free plus albumin-bound, used less often

When to test: timing matters

Testosterone follows a daily rhythm and is highest in the morning. Guidelines from the Endocrine Society and the AUA recommend early-morning testing, repeated on at least two separate days, before diagnosing low testosterone. Acute illness can temporarily lower levels, so avoid testing when you're sick.

How to prepare

• Book an early-morning appointment at your nearest Quest or Labcorp location
• Follow any fasting instructions on your lab order. Some panels include fasting glucose or lipids
• Tell your clinician about every medication and supplement, including biotin, which can interfere with some lab tests
• If you work nights, ask your clinician about the best time to test

Tests often ordered alongside testosterone

• LH and FSH: show whether low testosterone starts in the testes or the pituitary
• SHBG: helps interpret total testosterone
• Prolactin: checked when LH is low or normal with low testosterone
• CBC: a baseline hematocrit, important before TRT
• PSA: for men in age groups where prostate monitoring is recommended
• A1C, lipids, TSH: when symptoms or history suggest metabolic or thyroid issues

Understanding your results

Reference ranges vary by laboratory. The AUA uses total testosterone below 300 ng/dL as a reasonable cutoff to support a diagnosis when symptoms are present. One low result isn't enough. Neither is a "low-normal" number without symptoms. Your clinician interprets results with your symptoms, SHBG, LH/FSH and history.

Where to get tested in Houston

Quest Diagnostics and Labcorp both run patient service centers throughout Greater Houston, from Katy and Cypress to Pearland, Clear Lake and The Woodlands. Use the official locators: Quest · Labcorp. When you start with TRT Houston, we send your lab order electronically and review results with you by video.

After the test

If your results suggest low testosterone, the next step is confirmation and a search for causes. If treatment is appropriate, see how testosterone replacement therapy in Houston works. If results are normal but you still feel off, a broader hormone evaluation may help.