DHT test: what dihydrotestosterone measures and where it falls short

DHT is short for dihydrotestosterone. It is made from testosterone, and it has its own blood test. Most men with questions about low testosterone do not need it. This page explains what it measures and why its limits matter.

DHT

A single DHT test, for when a clinician has asked for DHT specifically.

$189

See this test at HealthLabs

Price checked October 2026. Not available in ND, RI, NY, NJ, MD and HI. We earn a commission on sales.

What the test measures

An enzyme called 5-alpha reductase converts testosterone into DHT. Testosterone and DHT both bind the androgen receptor. Testosterone has about half the affinity of DHT, which is largely made up for by its much higher blood levels. Serum DHT levels reflect, at least to a point, its activity in the body (Sansone et al., 2021).

Who might consider it

DHT is measured in specific clinical settings. A laboratory paper lists assessment of patients with ambiguous genitalia or hirsutism, and monitoring treatment with 5-alpha reductase drugs for prostate disorders (Steroids, 2008). Those are decisions for a clinician, not for a first-time buyer.

In a study of men seen in an andrology clinic, 635 completed an erectile function questionnaire and 574 an aging-symptoms questionnaire. In men whose testosterone was normal, DHT predicted scores on the aging-symptoms questionnaire. The adjusted analysis did not find the same link for erectile function scores. The authors concluded that DHT measurement “might be helpful once the diagnosis of hypogonadism has been ruled out but should not be routinely included in the primary diagnostic process” (Sansone et al., 2021). That is one retrospective, cross-sectional study, not a guideline.

The Endocrine Society’s guideline for diagnosing low testosterone centers on total and free testosterone, then LH and FSH (Bhasin et al., 2018). Start with the testosterone test guide, then use free vs total testosterone if you want to understand the options. If your question is about hair loss, see a clinician. This page covers the blood test only.

How to prepare

The seller’s page for this test doesn’t state a fasting rule. Follow the instructions on your lab order. Tell the person drawing your blood about all medicines and supplements, including any 5-alpha reductase drug. Don’t stop any medicine unless your clinician says to.

The seller’s page says the test needs a blood draw from the arm.

What a result can and can’t tell you

Labs set their own ranges, so use the range printed on your report.

The method matters. In one comparison, DHT measured by radioimmunoassay ran much higher than DHT measured by liquid chromatography-tandem mass spectrometry, and the authors concluded that serum DHT measured by any radioimmunoassay method overestimates the level (Steroids, 2008). That comparison is an older one.

What a DHT result can’t do:

• It can’t diagnose low testosterone.
• It can’t be compared across labs without care.

If a result is outside the range, take it to a clinician. Don’t change a medicine because of one number.