Testosterone is the primary male sex hormone, produced mainly by the testes and, in smaller amounts, by the adrenal glands.

It regulates sexual development, muscle mass, bone density, red blood cell production, and mood.

Clinical uses include:

Diagnosing hypogonadism (low testosterone levels).

Evaluating delayed or precocious puberty.

Investigating infertility, erectile dysfunction, and decreased libido.

Detecting androgen‑secreting tumors.

Monitoring hormone replacement therapy.

Often performed alongside Free Testosterone, LH, FSH, and SHBG tests for a complete hormonal profile.

Analyte: Total Testosterone in serum (ng/dL).

Normal Range (varies by lab):

Adult men: ~300–1000 ng/dL

Adult women: ~15–70 ng/dL

Abnormal Findings:

Low testosterone: Hypogonadism, pituitary/hypothalamic dysfunction, chronic illness, certain medications.

High testosterone: Androgen‑secreting tumors, polycystic ovary syndrome (PCOS), anabolic steroid use.

Clinical Use:

Provides a direct measure of androgen status.

Helps guide diagnosis and management of reproductive and endocrine disorders.

Supports urology, endocrinology, and gynecology evaluations.