Dihydrotestosterone (DHT)
The most potent androgen (male-type hormone), made from testosterone by an enzyme in the skin, hair follicles and prostate. It drives effects such as male-pattern hair loss, unwanted hair growth in women, and prostate enlargement, and is essential for male sexual development.
What it measures
Dihydrotestosterone (DHT) is a hormone made from testosterone by the enzyme 5-alpha-reductase, mostly in target tissues — the skin, hair follicles, prostate and genitals. Although it circulates at lower levels than testosterone, DHT binds the androgen receptor far more strongly, making it the most potent androgen in the body. Before birth and at puberty it is essential for the development of male external genitalia and many features of male maturation. In adults, DHT is the key androgen acting on hair follicles: on the scalp it causes male-pattern hair loss (androgenetic alopecia), while on the face and body it promotes hair growth — which is why women with excess androgens can develop hirsutism. In the prostate, DHT drives the gland's growth, which is why the enlargement of benign prostatic hyperplasia is treated with drugs (5-alpha-reductase inhibitors) that block its production. Measuring DHT is far less common than measuring testosterone; it is used in specialist assessment of certain disorders of sexual development, in men with a 5-alpha-reductase deficiency, when monitoring these blocking drugs, and occasionally in working up androgen excess. It is always interpreted alongside testosterone rather than alone.
What a high value can mean
- Androgen excess — with a high testosterone, can contribute to hirsutism and acne (as in PCOS or an androgen-producing source).
- Anabolic steroid or androgen use.
- A relatively high DHT-to-testosterone ratio — reflects active conversion in tissues, relevant in hair loss and prostate growth.
What a low value can mean
- 5-alpha-reductase deficiency — an inherited inability to convert testosterone to DHT, affecting male sexual development.
- Treatment with a 5-alpha-reductase inhibitor — the expected, intended effect of these drugs for prostate enlargement or hair loss.
- Low testosterone (hypogonadism) — less substrate to convert.
When to discuss with a doctor
DHT is a specialist test, not part of a routine hormone panel — testosterone is the usual measure of androgen status. DHT is checked in specific situations: assessing certain disorders of sexual development or a suspected 5-alpha-reductase deficiency, monitoring the drugs used for prostate enlargement or hair loss that block DHT, and occasionally as part of working up androgen excess causing hirsutism or hair loss. Because it is made and acts largely within tissues, a blood DHT does not always capture what is happening at the hair follicle or prostate, so it is interpreted carefully and alongside testosterone. Mediora.AI shows DHT alongside testosterone, free testosterone and SHBG so the androgen pattern reads together; the interpretation belongs with your doctor or endocrinologist.