TRT in the UK: A Complete Guide to Testosterone Replacement Therapy

Explore TRT with Heracles: specialist expertise, clear monthly plans, prescribed medication, scheduled blood tests and doctor reviews.

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TRT replaces testosterone when your body is not producing enough and a clinician confirms treatment is appropriate. It can improve symptoms of testosterone deficiency, with ongoing monitoring to keep your care on track.

Heracles combines specialist expertise, clear monthly plans and scheduled blood tests and doctor reviews. Explore Heracles TRT care or start your free switch consultation.

Private TRT in the UK: assessment, costs and ongoing care

Know the route into care and what you will pay at each stage. A private TRT assessment brings your symptoms, medical history, blood results and fertility plans together before a treatment decision. Diagnosis requires consistently low testosterone alongside relevant symptoms; a single result does not settle it. Endocrine Society assessment guidance.

Starting a TRT assessment

Heracles' published pathway starts with a £29.99 home testosterone test. If the result is low, a £129.99 fuller blood panel checks the wider picture. Your clinician confirms the tests and review needed for your circumstances. These initial costs are separate from the monthly treatment plan.

If TRT is prescribed, gel plans start from £90 per month and injectable plans from £105 per month. Prescribed medication, applicable supplies, scheduled blood tests and doctor reviews are included. Plans are billed monthly with a three-month minimum; extra testing, hCG and additional services are priced separately.

Already receiving prescribed TRT?

Start with a free Heracles switch consultation. Have your current prescription, treatment schedule and blood reports ready. The clinician reviews whether your existing tests can support the transfer and explains any further requirements before you pay.

Heracles was co-founded by Professor Suks Minhas and Professor Tet Yap, consultant urologists and andrologists, with a wider team in hormones, nutrition and sexual health. Meet the specialists behind your care.

Explore NHS and private access routes, compare monthly prices and inclusions, or use our guide to choosing Heracles. See the Heracles TRT service for the current care pathway.

The short answer

UK treatment options include gels and injections. Your clinician recommends an option after reviewing symptoms, repeat testosterone tests, the cause of deficiency, fertility plans and safety checks. Monitoring continues throughout treatment.

What is TRT?

TRT provides exogenous testosterone—testosterone from outside the body—to restore levels into a physiological range. It can be absorbed through the skin or delivered as an injection. Different testosterone esters and delivery systems change how quickly it enters the circulation and how often it is administered.

Replacement is different from stimulating the testes to produce more testosterone. Once exogenous testosterone is present, the hypothalamus and pituitary reduce luteinising hormone and follicle-stimulating hormone. Natural testicular testosterone production and spermatogenesis fall as a result.

Treatment should improve clinically relevant symptoms and health consequences at a safe physiological exposure without avoidable adverse effects. A laboratory number alone is not a sufficient outcome.

Who may be eligible for TRT in the UK?

A typical evidence-based assessment looks for all of the following:

  • symptoms or signs compatible with testosterone deficiency;
  • low morning, fasting total testosterone confirmed on a separate day;
  • SHBG and calculated free testosterone considered when the total result is borderline or SHBG may be abnormal;
  • investigation of primary, secondary or functional hypogonadism;
  • treatment of reversible contributors where appropriate;
  • a discussion of current and future fertility; and
  • no contraindication that makes testosterone unsuitable.

The Society for Endocrinology joint position statement considers two morning, fasting results below 8 nmol/L likely to represent hypogonadism in a symptomatic man. Results of 8–12 nmol/L require careful clinical correlation. Values above 12 nmol/L are not usually consistent with hypogonadism. The EAU uses below 12 nmol/L, repeated on at least two occasions alongside symptoms, as a threshold for late-onset hypogonadism.

When might TRT not be the right treatment?

TRT may be inappropriate when the testosterone result is normal, symptoms have a more likely explanation or the underlying suppression is better addressed directly. Examples include untreated sleep apnoea, marked under-fuelling, acute illness, a medicine effect, obesity-related functional suppression or poorly controlled metabolic disease, although some men will still need specialist hormone treatment after those factors are addressed.

TRT is also not the standard treatment for a man actively trying to conceive. It suppresses sperm production. Selected men with secondary hypogonadism may instead need specialist approaches that stimulate endogenous testosterone and spermatogenesis.

Who should not start TRT?

Contraindications and cautions vary slightly between guidelines and product information. The EAU lists the following main contraindications:

  • locally advanced or metastatic prostate cancer;
  • male breast cancer;
  • an active desire to have children;
  • haematocrit of 54% or higher; and
  • uncontrolled or poorly controlled congestive heart failure.

Severe lower urinary tract symptoms, baseline haematocrit around 48–50% and a family history of venous thromboembolism require additional caution and assessment. Individual UK product information also lists formulation-specific contraindications, excipient allergies and medical precautions.

Prostate history, breast symptoms, urinary symptoms, cardiovascular disease, previous thrombosis, smoking, hypertension, sleep apnoea, migraine, epilepsy, liver or kidney disease and use of anticoagulants should be discussed with the prescriber. The presence of a condition does not always produce the same decision, but hiding it prevents safe prescribing.

What TRT options are available in the UK?

The exact formulary and stock position can change. The comparison below describes major UK-licensed routes, not a personal recommendation.

FormulationTypical practical patternPotential advantagesImportant limitations
Testosterone gelApplied to clean, dry skin every day according to the product instructionsNeedle-free; dose can be adjusted; treatment can be stopped quickly if neededDaily routine; variable absorption; skin irritation; transfer risk to partners or children
Shorter-acting intramuscular testosterone ester injectionAdministered at intervals determined by the licensed product and responseLess frequent than daily gel; established productsInjection discomfort; peaks and troughs may occur; haematocrit can rise; some products contain oils or excipients relevant to allergy
Long-acting testosterone undecanoate injectionDeep intramuscular injection administered by a healthcare professional at long intervalsInfrequent dosing; avoids daily applicationLarge-volume clinic injection; slow administration and observation requirements; slower to reverse; rare injection-related pulmonary oil microembolism risk

Testosterone gels

UK products include testosterone gels such as Testogel and Tostran. They are applied daily to product-specific skin sites. Hands must be washed afterwards, the gel allowed to dry and the site managed to prevent transfer through skin contact. The patient information leaflet controls the exact application, washing, showering and contact instructions.

Gels can be useful when a reversible option is preferred or injection peaks are problematic. Absorption varies, so a standard number of pumps is not a universal dose. Blood-test timing and dose adjustment must follow the particular product.

Sustanon 250

Sustanon is a mixture of four testosterone esters in an oily intramuscular injection. Its UK product information states that the dose should be adjusted to the individual's response. It contains arachis oil and is contraindicated in people allergic to peanuts or soya.

Online clinics sometimes advertise more frequent or subcutaneous micro-dosing schedules. Any off-label route or schedule needs a prescriber’s explanation and monitoring plan. Follow your prescribed instructions.

Testosterone enantate

Testosterone enantate is a licensed intramuscular depot injection for confirmed male hypogonadism. Its product information describes administration intervals that are individualised using symptoms and trough testosterone levels.

The published intramuscular instructions should not be silently replaced by a different route. If a clinician recommends an off-label route or interval, the patient should be told what is off label, why it is being used, what evidence supports it and how it will be monitored.

Long-acting testosterone undecanoate

Nebido and other testosterone undecanoate injections are long-acting intramuscular preparations administered under healthcare-professional guidance. UK product information requires very slow, deep gluteal injection and includes precautions intended to reduce pulmonary oil microembolism and anaphylactic reactions.

The long interval is convenient for some men, but the medicine is not easy to remove once administered. That makes diagnostic confidence and early safety assessment especially important.

What about testosterone cypionate, creams, capsules or pellets?

These may appear on private-clinic websites or in overseas content, but licensing, availability, route and evidence differ in the UK. Ask for the exact product, manufacturer, route and regulatory status rather than treating every form of “TRT” as interchangeable.

How is a TRT option chosen?

Your clinician considers the diagnosis, fertility plans, medical history and practical preferences. Gel needs a daily routine and precautions around skin contact; injections need an agreed schedule and appropriate training or clinical administration. Your plan also accounts for monitoring, supply and cost.

What benefits can TRT provide?

Benefits depend on how low testosterone was before treatment, the symptom being measured and whether another condition is responsible. Evidence is strongest for improvement in sexual desire and other sexual symptoms in appropriately selected hypogonadal men. TRT may also:

  • improve anaemia caused by testosterone deficiency;
  • support increases in lean mass and reductions in fat mass;
  • improve bone density over time;
  • improve some aspects of mood or wellbeing; and
  • help maintain male secondary sexual characteristics.

Changes do not occur on one schedule. Sexual symptoms may begin to improve within months, while body composition and bone effects take longer. Energy, concentration and erectile function are less predictable because they often have multiple causes.

What are the side effects and risks?

Raised haematocrit

Testosterone stimulates red blood cell production. Haematocrit can rise too far, increasing concern about blood viscosity and thrombotic risk. Injectable formulations tend to cause erythrocytosis more often than topical formulations.

The EAU advises monitoring testosterone and haematocrit at three, six and 12 months after treatment begins and annually thereafter. A haematocrit above 54% requires treatment adjustment or withdrawal and may require venesection, followed by reassessment before treatment is reintroduced.

Fertility suppression and testicular change

TRT suppresses LH, FSH and intratesticular testosterone. Sperm count can fall substantially or reach zero, and testicular volume may reduce. The effect is often reversible after stopping, but recovery can take months or longer and is not guaranteed on a personal timetable.

hCG or selective oestrogen receptor modulators are sometimes used in specialist fertility-preserving pathways, but they do not make fertility risk disappear. Their indication, UK licensing status, evidence and monitoring must be explained separately.

Skin, breast and fluid-related effects

Acne, oily skin, hair changes, breast tenderness or gynaecomastia, ankle swelling and weight change can occur. Gel can irritate the skin and can transfer testosterone to another person if instructions are not followed.

Injection-specific effects

Pain, bruising and inflammation can occur. Oily injections have rare but important risks if material enters the circulation. Long-acting testosterone undecanoate has specific administration and observation precautions. A patient should be trained only in a route the prescriber and product pathway allow.

Prostate and urinary health

Testosterone treatment can change PSA and prostate volume. Current EAU evidence does not show that physiological testosterone therapy causes prostate cancer, but men with active advanced disease are not candidates and long-term data have limits. Baseline risk assessment and appropriate follow-up remain necessary.

New difficulty urinating, blood in urine or semen, a marked PSA change or other concerning symptoms need clinical review rather than automatic dose adjustment.

Cardiovascular health

The EAU concludes that there is no substantive evidence that testosterone replaced to normal levels causes major adverse cardiovascular events, while advising caution and close monitoring in men with established cardiovascular disease, venous thromboembolism or heart failure. Testosterone can also increase blood pressure or fluid retention in some settings.

Does TRT affect hair loss, oestrogen or sleep apnoea?

Testosterone can be converted to dihydrotestosterone and oestradiol. In genetically susceptible men, androgen exposure may accelerate male-pattern hair loss. Oestradiol is necessary for male health, and a laboratory value should not be “crashed” simply because it is labelled oestrogen. Symptoms, assay quality and the overall hormone pattern matter.

Sleep apnoea deserves assessment because untreated disease can mimic low-testosterone symptoms and can increase the risk of raised haematocrit. Product information and guidelines differ in how they frame the evidence, so a man with suspected or poorly controlled sleep apnoea needs an individual plan rather than a blanket reassurance.

What happens before the first prescription?

A safe baseline normally includes:

  1. symptoms, goals and a clinical history;
  2. two valid low testosterone measurements;
  3. SHBG and calculated free testosterone where indicated;
  4. LH, FSH and sometimes prolactin to classify the cause;
  5. examination or further investigation where the history requires it;
  6. fertility discussion and, when relevant, semen analysis or fertility referral;
  7. full blood count and haematocrit;
  8. prostate assessment appropriate to age, symptoms and risk;
  9. blood pressure and cardiovascular review;
  10. review of sleep apnoea, urinary symptoms and thrombotic risk; and
  11. a formulation-specific explanation of licensed and off-label use.

The prescription should include an agreed target, administration instructions, follow-up schedule and route for urgent concerns.

How is TRT monitored?

Monitoring must match the formulation and the patient. A useful structure is:

StageWhat may be reviewed
BaselineSymptoms, testosterone pattern, cause, fertility, haematocrit, prostate risk, blood pressure, metabolic and cardiovascular factors
Around 3 monthsSymptoms, adverse effects, administration, correctly timed testosterone, haematocrit; PSA or other markers where indicated
Around 6 monthsBenefit, safety, testosterone and haematocrit; formulation or dose problems; relevant prostate review
Around 12 monthsContinued indication, symptom goals, testosterone, haematocrit, blood pressure, metabolic and prostate monitoring as appropriate
Annually when stableContinued benefit-risk review and guideline-appropriate safety monitoring; more often for higher-risk men

Timing of the testosterone sample changes by product. A trough result before an injection and a sample taken soon after an injection do not answer the same question. Gel levels also depend on application timing and contamination precautions. The clinical service should give written instructions for each formulation.

Monitoring should ask whether the original symptom improved. A normal result without benefit may mean the symptom had another cause. Continuing indefinitely because the number changed is not patient-centred care.

Can you stop TRT?

Yes, but the consequences depend on why treatment was started, the formulation, duration and the body's capacity to recover endogenous production. The original symptoms can return, and recovery of the hormonal axis and sperm production may take time.

There is no universal taper or “post-cycle therapy” suitable for self-management. Men considering a stop should agree a plan with the prescriber, particularly when fertility, severe symptoms or long-acting injections are involved.

NHS TRT vs private TRT

You can start with your NHS GP or choose a private assessment. Heracles offers a direct online route into testing and doctor review, followed by a monthly care plan if TRT is prescribed. Compare the NHS and Heracles pathways.

Why choose Heracles for TRT?

Choose care with experienced clinicians, a thorough assessment and continuing monitoring. Heracles brings prescribed TRT medication, applicable supplies, scheduled blood tests and doctor reviews into a clear monthly plan.

Heracles was co-founded by Professor Suks Minhas and Professor Tet Yap. Our team brings together expertise in urology, andrology, endocrinology, nutrition and sexual health. Meet the specialists behind your care.

Start your testosterone assessment or arrange your free switch consultation.

More common questions

Does TRT build muscle?

Correcting genuine deficiency can increase lean mass and support strength, especially with appropriate training and nutrition. TRT should not be prescribed to enhance muscle or performance in a man without hypogonadism.

Is TRT safe for the heart and prostate?

Current evidence is more reassuring than older warnings when testosterone is replaced physiologically in properly selected men, but it does not remove the need for cardiovascular and prostate assessment. Men with active advanced prostate cancer, uncontrolled heart failure or significant risk factors require specific decisions.

What happens if haematocrit becomes too high?

The clinician may pause or reduce treatment, change formulation, investigate contributory causes and arrange venesection when clinically required. A value above 54% requires action under EAU guidance.

The expertise behind Heracles

Heracles was co-founded by Professor Suks Minhas, Consultant Urologist and Andrologist, and Professor Tet Yap, Professor of Urology at King's College London. Our wider team brings together endocrinology, fertility, nutrition and psychosexual health. Meet the people behind your care.

Already on TRT? Your Heracles switch consultation is free. Injectable plans start at £105 per month, including prescribed medication, applicable supplies, scheduled blood tests and doctor reviews. Explore switching and see the full plan details.