The 5-Alpha Dihydrotestosterone (DHT) serum test measures the level of DHT, a potent androgen hormone derived from testosterone via the 5-alpha reductase enzyme, in blood serum. It is used to assess androgen metabolism and diagnose conditions related to hormonal imbalances.

Purpose: Evaluates 5-alpha reductase deficiency (affecting male sexual development), monitors 5-alpha reductase inhibitor therapy (e.g., for hair loss or prostate issues), and assesses conditions like male pattern baldness, benign prostatic hyperplasia (BPH), prostate cancer, hirsutism, or polycystic ovarian syndrome (PCOS).
Sample Type: Serum (blood drawn from a vein, centrifuged, and separated within 1–2 hours; stored at -20°C if delayed).
Procedure: Requires no special preparation (e.g., fasting), though avoiding steroids or discussing medications with a doctor is advised. A 0.5–1 mL serum sample is typically needed.
Detection: Uses techniques like LC-MS/MS for accurate quantification. Normal ranges vary (e.g., 0.32–1.64 nmol/L for adult males), with results interpreted based on age, sex, and clinical context.
Limitations: DHT levels fluctuate (e.g., higher in puberty), and serum levels may not reflect tissue-specific activity. An elevated testosterone-to-DHT ratio can indicate 5-alpha reductase deficiency.