Private testosterone blood test,
Harley Street, London.

A focused testosterone test measures total testosterone, free testosterone (calculated from SHBG and albumin) and DHT. Where a result is low or symptoms warrant it, we add LH and FSH to classify the cause, and oestradiol or prolactin to investigate secondary causes. At WMG Health the panel is built around your specific question, drawn at 134 Harley Street and interpreted by a GMC-registered doctor against BSSM guidance.

Yes. A testosterone test is a blood test: testosterone is measured from a venous blood sample, ideally drawn in the morning. The terms testosterone test, testosterone blood test and testosterone level test all describe the same thing. At WMG Health it is drawn at 134 Harley Street, London and interpreted by a GMC-registered doctor, with total testosterone reported within 24 hours.

Testosterone follows a daily rhythm, peaking in the early morning and falling through the day, so a sample drawn in the afternoon can read misleadingly low even in a healthy man. BSSM guidance is a fasting morning sample drawn between 7 and 11 AM. Food, and glucose in particular, transiently lowers testosterone, which is why the draw is done fasting with water only.

Total testosterone measures all the testosterone in your blood, most of which is bound to SHBG and albumin and not available to your tissues. Free testosterone is the small unbound fraction that is biologically active. When total testosterone sits in the grey zone (8 to 12 nmol/L), the free testosterone, calculated from total testosterone, SHBG and albumin, is what clarifies whether you are genuinely deficient. This is why measuring SHBG alongside total testosterone matters.

BSSM regards a fasting morning total testosterone above 12 nmol/L as generally normal and below 8 nmol/L as supporting a diagnosis of testosterone deficiency. Between 8 and 12 nmol/L is a grey zone where the calculated free testosterone (deficiency supported below approximately 0.225 nmol/L) and your symptoms guide interpretation. A number in isolation does not make a diagnosis: it is read alongside symptoms, SHBG, LH and FSH.

For a new diagnosis of testosterone deficiency, yes. BSSM recommends confirming a low result with a second fasting morning sample drawn on a separate day before deficiency is diagnosed, because testosterone varies day to day and a single low reading can be transient (acute illness, poor sleep and stress all lower it). If you are already on treatment and testing for monitoring, a single timed sample is usually sufficient.

Men on testosterone replacement are typically monitored with total testosterone (timed to your regimen, for example trough level before the next injection), haematocrit and full blood count (testosterone raises red cell mass, and a rising haematocrit is the commonest reason to adjust a dose), plus PSA where age-appropriate and oestradiol if symptoms suggest it. We tailor the monitoring panel to your preparation and how long you have been on it.

Yes. In women, testosterone is measured mainly to investigate androgen excess: unwanted hair growth, scalp hair thinning, acne or suspected PCOS, where a raised DHEAS points to an adrenal source and raised testosterone to an ovarian or mixed picture. It is also relevant to low libido assessment. The interpretation and reference ranges differ entirely from men, which is why results are always read by a clinician rather than against a lab range alone.

Our focused Testosterone Panel (total testosterone, free testosterone and DHT) is £199. Where a result needs its cause classified we add LH, FSH, SHBG, oestradiol or prolactin, and because that marker list is tailored per patient we confirm the exact price in writing before booking. Total testosterone and DHT are reviewed within 24 hours; calculated free testosterone can take up to 48 hours as it depends on the SHBG result.