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Eight-marker testosterone panel for natural monitoring or TRT safety checks — including oestradiol, haematocrit, and PSA.
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An eight-marker testosterone monitoring panel for men tracking natural testosterone health or on testosterone replacement therapy.
Whether you are monitoring testosterone naturally, optimising it through lifestyle, or already on TRT, the Testosterone Optimisation Panel provides the eight key markers needed to understand and safely manage your testosterone status.
Total and free testosterone (calculated via SHBG) assess androgen levels and bioavailability. LH and FSH reveal whether the pituitary-testicular axis is functioning normally — in men on TRT, these are suppressed (expected) and their levels confirm whether the therapy is affecting natural testosterone production. Oestradiol is essential: testosterone aromatises to oestradiol, and monitoring this ratio is critical for wellbeing and safety on TRT. Haematocrit (packed cell volume) rises with testosterone and excessive elevation increases stroke risk — a safety marker essential for anyone on TRT. PSA is included because testosterone stimulates prostate tissue and should be monitored.
This panel is used quarterly to six-monthly by men on TRT for safety monitoring, and annually by men managing testosterone naturally. Morning venous draw required. GMC-physician reviewed results within 3 to 5 working days.
Understand what each marker measures, why it matters, and what the science says — not just a list of numbers.
Primary androgen; the core efficacy marker for TRT and natural testosterone assessment.
Biologically active fraction; a key determinant of symptom response on TRT.
Binding protein controlling free testosterone bioavailability; varies with dose, route, and individual physiology on TRT.
Suppressed by exogenous testosterone on TRT; confirms TRT effect and natural production suppression.
Also suppressed on TRT; relevant for fertility preservation monitoring in TRT users.
Produced by aromatisation of testosterone; excess causes gynaecomastia and water retention; deficiency causes bone and mood problems.
Proportion of blood occupied by red blood cells; rises with testosterone and must be monitored to prevent thrombotic risk.
Prostate gland marker; monitored in TRT users since testosterone stimulates prostate tissue.
This panel is designed for adults who want a comprehensive, evidence-based picture of their metabolic health — not a GP referral panel.
Men on testosterone replacement therapy requiring regular safety monitoring
Those managing testosterone naturally through lifestyle and wanting periodic assessment
Men who have recently started TRT and want to confirm therapeutic levels
Those concerned about haematocrit or oestradiol on TRT
Testing timing relative to TRT injection or gel application significantly affects results. For injectable testosterone (e.g. Sustanon, Nebido), testing at trough (immediately before the next injection) gives the most clinically meaningful reading for dose adequacy. For testosterone gel, morning testing 4 to 6 hours after application gives a typical peak value. Always note your dosing schedule and last dose date in your profile. Haematocrit above 52% is generally a threshold requiring medical review and possible treatment break or dose reduction. LH and FSH will be suppressed on TRT — this is expected and does not indicate a problem. PSA should be interpreted age-specifically. Free testosterone is calculated, not directly measured.
From order to physician-reviewed report in as little as three working days.
Three options designed to fit your schedule, location, and preference — all producing a laboratory-standard sample.
Adults 18+ in mainland UK. Not suitable if you have had a transfusion in the last 3 months.
Order anytime; kit dispatched within 24 hours Mon–Fri.
Allow 24–48 hours for sample transit on top of lab processing time.
Adults 18+ within 20 miles of a serviced city centre.
Mon–Sun, 06:00–20:00. Next-day booking typical.
Sample reaches the lab within 24 hours of collection.
Adults 16+ with photo ID. Paediatric draws by appointment at selected sites.
Mon–Fri, with Saturday hours at most metropolitan locations.
Samples processed same-day at the receiving clinic.
Every test is processed in a UKAS ISO 15189-accredited laboratory, overseen by GMC-registered physicians, and governed by UK GDPR. No overseas processing, no offshore data.
Follow these guidelines to ensure accurate, reproducible results. Most markers are sensitive to recent food, exercise, and sleep.
Can't find your answer? Our clinical support team is available Monday to Friday, 9am–5pm.
Contact supportHaematocrit (HCT) refers to the percentage of blood volume occupied by red blood cells. Testosterone stimulates erythropoiesis (red blood cell production), which can raise haematocrit — a useful effect at low levels, but a thrombotic risk at higher levels. Most TRT guidelines recommend a threshold of 52 to 54% as the upper limit before intervention. If haematocrit exceeds 52%, options include a dose reduction, a treatment break, switching to a different administration route (which may cause less erythrocytosis), or therapeutic phlebotomy (blood donation or venesection) under medical guidance. Regular monitoring prevents this becoming a safety issue.
Oestradiol in men on TRT requires balance — not too high (causing water retention, gynaecomastia, mood instability, and cardiovascular risk) and not too low (causing joint pain, poor bone density, low libido despite adequate testosterone, and cognitive decline). A commonly used target range for men on TRT is 80 to 150 pmol/L, though this varies by individual sensitivity and the testosterone dose used. If oestradiol is significantly elevated, strategies include dose reduction, switching to a more frequent lower-dose injection schedule (which tends to produce lower E2 spikes), or using a low-dose aromatase inhibitor under medical supervision.
Testosterone stimulates prostate tissue, and PSA can rise modestly after starting TRT. A sudden or large rise in PSA (e.g. above 1.4 ng/mL within 12 months of starting TRT) warrants medical review to exclude prostate cancer, which is not caused by TRT but can be stimulated by it if already present. For this reason, a baseline PSA before starting TRT and regular annual monitoring thereafter are recommended. Men with a prior diagnosis of prostate cancer are generally not candidates for TRT without specialist oncology input.
Exogenous testosterone suppresses the pituitary’s output of LH and FSH, which are the signals that stimulate sperm production. Most men on TRT experience significantly reduced or absent sperm production (azoospermia) within months of starting treatment. This is largely reversible on stopping TRT, though recovery can take 6 to 18 months and is not guaranteed in all cases. Men who wish to preserve fertility while on TRT can discuss adjunctive HCG (human chorionic gonadotrophin) therapy with a specialist, which mimics LH and maintains testicular testosterone production and spermatogenesis.
During the initiation phase of TRT (first 3 to 6 months), testing every 6 to 8 weeks allows dose titration to achieve target testosterone levels and verify that haematocrit, oestradiol, and PSA are within safe ranges. Once on a stable, well-tolerated dose, testing every 3 to 6 months is appropriate for ongoing safety monitoring. The physician report will recommend a specific retesting interval based on your results. Men who are not on TRT but are monitoring testosterone annually for natural decline typically test once or twice per year.
When exogenous (external) testosterone is administered, the brain detects elevated circulating testosterone and reduces its signalling through the hypothalamic-pituitary axis — specifically reducing LH and FSH output. This is a normal and expected physiological response called negative feedback. On TRT, suppressed LH and FSH are a confirmation that the treatment is being absorbed and is circulating — not a cause for concern. However, suppressed LH also means the testes are no longer producing their own testosterone, which explains why testicular volume often decreases on TRT and why fertility is affected.
