Free dihydrotestosterone (DHT) represents the biologically active, unbound fraction of DHT not associated with sex hormone-binding globulin (SHBG) or albumin, measured via liquid chromatography-mass spectrometry (LC/MS) following equilibrium dialysis for high analytical specificity. DHT is a potent androgen derived primarily from the peripheral conversion of testosterone by the enzyme 5-alpha reductase, with approximately 3–10 times greater androgenic potency than testosterone at the androgen receptor. This assay provides a more physiologically relevant measure of androgenic activity than total DHT, particularly in clinical contexts where SHBG levels may be altered. DHT is synthesized predominantly in peripheral tissues—including the prostate, skin, and hair follicles—through the action of 5-alpha reductase types 1 and 2, and binds the androgen receptor with high affinity and slow dissociation. Unlike testosterone, DHT cannot be aromatized to estrogen, making it a purely androgenic signal critical for virilization, prostate growth, and male-pattern hair follicle miniaturization. Free DHT, constituting roughly 0.5–3% of total DHT, is the fraction available for cellular uptake and receptor binding, and its concentration is influenced by SHBG levels, liver function, and 5-alpha reductase activity.
Free DHT is a measurement of the active, unbound form of dihydrotestosterone—a powerful male hormone—in your blood. DHT plays important roles in hair growth, skin oil production, and prostate health. This specialized test uses advanced laboratory techniques to give a very accurate picture of how much DHT is actually available to affect your body's cells. Your doctor may order this test to investigate symptoms of too much or too little androgen activity, or to monitor the effects of certain medications. Results should always be reviewed alongside other hormone tests and your overall health picture.
When elevated: Elevated free DHT may indicate increased 5-alpha reductase activity, exogenous androgen use, or conditions associated with androgen excess such as polycystic ovary syndrome (PCOS) in women or androgenic alopecia and BPH in men. High levels may contribute to prostate tissue proliferation, sebaceous gland hyperactivity, and androgen-dependent hair follicle miniaturization. When low: Low free DHT may reflect 5-alpha reductase deficiency (congenital or acquired), primary or secondary hypogonadism, or therapeutic suppression with 5-alpha reductase inhibitors. In males, chronically low DHT may be associated with impaired virilization, reduced prostate volume, and altered sexual function.
Free DHT may be of interest to strength athletes and those concerned with body composition, as DHT drives muscle protein synthesis and androgen receptor signaling in skeletal muscle. However, free DHT is primarily relevant for monitoring androgenic side effects (acne, hair loss, prostate health) rather than as a direct performance metric; total testosterone and training variables are more practical performance indicators for most athletes.
Turnaround Time
14 days (up to 19 days)
Fasting Required
No
Method
LC/MS/Dialysis
verifiedGold StandardMass spectrometry — higher accuracy, especially at low concentrations
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Your price
$105.00$190
1.8× less than retail
Versus the typical direct-to-consumer retail price for this test (illustrative — consumer prices vary by provider and region).
$105.00
$300.00
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