Androgens . Patient guide
Dihydrotestosterone (DHT) Blood Test
What is DHT
DHT (dihydrotestosterone) is a more potent androgen produced from testosterone by the enzyme 5-alpha reductase, primarily in hair follicles, prostate and skin. It is the key androgen driving male-pattern hair loss and female-pattern hair thinning.
This biomarker entry is being clinically reviewed by our team. The factual content draws on UK guidance (NICE, NHS, Royal Colleges and the relevant speciality society where cited).
Reference range
Reported in nmol/L. Final reports always carry the issuing laboratory's range, which is what your clinician will interpret against.
| Group | Range | Note |
|---|---|---|
| Adult men | 0.86 to 2.93 | nmol/L (varies by assay) |
| Adult women | 0.03 to 0.83 | |
| On finasteride (men) | expect suppression below baseline by roughly 70 percent |
What it is
DHT acts on the androgen receptor with roughly five times the functional potency of testosterone (a combination of higher binding affinity and slower dissociation), and is the dominant androgen at scalp follicles. Drugs such as finasteride (5-alpha reductase inhibitor type II) and dutasteride (types I and II) suppress DHT production.
Why a clinician would order it
In men: confirmation that finasteride or dutasteride is suppressing DHT as expected, particularly in inadequate-response situations. In women: in the work-up of androgenetic scalp thinning and PCOS / PMOS. Also as part of pre-treatment baseline for anyone considering hormonal treatment for hair loss.
If your level is outside the range
Symptoms of low DHT
- Reduced libido and erectile function (in men, with suppression below typical range)
What low can indicate. Effective treatment with a 5-alpha reductase inhibitor, or rare congenital deficiency.
Symptoms of high DHT
- Accelerated androgenetic alopecia (scalp thinning), prostate symptoms, in women: hirsutism and acne
What high can indicate. Genetic predisposition to androgenetic alopecia (relative, not absolute), exogenous DHT exposure (e.g. some “supplements”), androgen-secreting tumours (rare).
Testing tips
Morning sample (DHT follows the same diurnal rhythm as testosterone). If you are on finasteride or dutasteride, continue at your usual dose unless your prescriber has told you otherwise; testing on treatment is what we are interested in.
Where you can get this tested
Dihydrotestosterone is included in the following WMG Health panels. Same-day appointments at our Harley Street clinic, with results clinician-reviewed.
Want a specific combination of markers we do not have a panel for? Build a custom panel and our clinicians will design one for you.
Symptoms often investigated with Dihydrotestosterone
Dihydrotestosterone is commonly tested when patients present with the following symptoms. If any of these resonate with you, the linked guides explain what to look for and which test pathway is appropriate.
Related markers
Sources
UK guidance our clinicians use when interpreting this marker.
This page is general patient information, not personal medical advice. A GMC-registered clinician will review your results and tailor any interpretation to you. See our Editorial Policy for how we write and review content.
Common questions about DHT
What is a normal DHT range?
Adult men: 0.86 to 2.93 (nmol/L (varies by assay)). Adult women: 0.03 to 0.83. On finasteride (men): expect suppression below baseline by roughly 70 percent. Always interpret your own results against the laboratory range printed on your report, since assay-specific reference ranges vary.
What does a low DHT result mean?
Effective treatment with a 5-alpha reductase inhibitor, or rare congenital deficiency.
What does a high DHT result mean?
Genetic predisposition to androgenetic alopecia (relative, not absolute), exogenous DHT exposure (e.g. some “supplements”), androgen-secreting tumours (rare).
Do I need to fast or prepare for the DHT blood test?
Morning sample (DHT follows the same diurnal rhythm as testosterone). If you are on finasteride or dutasteride, continue at your usual dose unless your prescriber has told you otherwise; testing on treatment is what we are interested in.
Can I order a DHT blood test privately in London?
Yes. WMG Health offers DHT as part of bespoke panels and several pre-built panels at our 134 Harley Street clinic. Results are clinician-reviewed by a GMC-registered doctor within 4 hours for the most common assays. All panels are custom-built around your specific question; bookings via /contact/ or 020 3239 3378.