Key Takeaways
- The four main UK-licensed TRT options are Sustanon 250 (injection every 2–3 weeks), Nebido (injection every 10–14 weeks), Testogel (daily gel), and Tostran (daily gel).
- NHS TRT eligibility requires a morning serum testosterone below 8 nmol/L, or 8–12 nmol/L with clear symptoms (BSSM guidelines).
- Private TRT clinics accept lower thresholds and offer faster access; monthly costs: £50–£150 (gels) or £30–£80 (injections) plus consultation fees.
- Six-month total private TRT costs (including initial consultation, blood tests, and medication) range from approximately £500 to £1,200.
- All TRT requires ongoing monitoring of testosterone, oestradiol, and haematocrit every 3–6 months to manage risks such as polycythaemia and fertility suppression.
Introduction
The best TRT treatment in the UK depends on your lifestyle, budget, and how stable you need your hormone levels. The main licensed options are injections (Sustanon 250 and Nebido) and gels (Testogel and Tostran), with monthly private costs ranging from £20 to £70. This guide compares them directly, including NHS vs. private pathways, blood test thresholds, and a cost breakdown.
Low testosterone affects approximately 2 in 100 men under 60 and up to 5 in 100 over 60 in the UK[8], yet most men cannot access clear, unbiased comparisons of the licensed treatments available. Many online guides focus on US-centric clinic comparisons or affiliate listicles that ignore the specific medications and NHS pathways UK patients need. This article provides an unbiased, side-by-side comparison of the four main UK-licensed TRT medications—Sustanon 250, Nebido, Testogel, and Tostran—alongside private costs, NHS eligibility criteria, and blood test monitoring.
What Are the Main Types of TRT Available in the UK?
Testosterone replacement therapy replaces the testosterone your body no longer produces in sufficient amounts. In the UK, the four main licensed products are all available on the NHS and through private clinics. All four products are licensed by the Medicines and Healthcare products Regulatory Agency (MHRA) for testosterone replacement.
- Testosterone ester injections – Sustanon 250 (testosterone propionate, phenylpropionate, isocaproate, and decanoate) and Nebido (testosterone undecanoate).
- Topical gels – Testogel (testosterone 1% gel) and Tostran (testosterone 2% gel). A testosterone patch (Andropatch) is also licensed but rarely used due to skin irritation.
- Subcutaneous pellets (Testopel) – implanted under the skin every 4–6 months; licensed but not widely available in the UK.
- Oral testosterone (testosterone undecanoate capsules) – available but less commonly prescribed due to variable absorption and liver metabolism.
Two licensed products dominate the UK market: Sustanon 250 (the oldest, most affordable injection) and Testogel (the most prescribed topical option). Nebido is preferred for patients who want fewer injections, and Tostran offers a higher-concentration gel requiring smaller volumes.
TRT Injections Compared: Sustanon 250 vs. Nebido
Intramuscular testosterone injections deliver a rapid peak followed by a gradual decline. The choice between Sustanon 250 and Nebido affects your injection frequency, cost, and how stable your levels are.
Sustanon 250
Sustanon 250 is a short- to medium-acting blend of four testosterone esters. It is injected intramuscularly every 2 to 3 weeks.
| Attribute | Details |
|---|---|
| Frequency | Every 2–3 weeks (patient administered or nurse) |
| Typical dose | 1 mL (250 mg) per injection |
| Peak testosterone | ~30–40 nmol/L 24–48 hours post-injection |
| Trough level after 2 weeks | May drop below 12 nmol/L |
| NHS list price (per injection) | ~£7–£9 (free on NHS prescription) |
| Private cost (per injection) | £20–£30 |
| LH/FSH suppression | Significant – fertility declines quickly |
Pros: Very low cost; widely available; short half-life allows quick withdrawal if side effects occur.
Cons: Hormonal peaks and troughs can cause mood swings, energy crashes, and libido fluctuations; requires more frequent injections; higher risk of polycythaemia at peak.
Nebido (Testosterone Undecanoate)
Nebido is a long-acting testosterone undecanoate injection given every 10–14 weeks. It requires a trained healthcare professional to administer due to the large volume (4 mL).
| Attribute | Details |
|---|---|
| Frequency | Every 10–14 weeks (clinic-administered only) |
| Typical dose | 1000 mg per injection (4 mL) |
| Testosterone stability | Steady state reached after 3–5 loading doses |
| Trough level at end of interval | Typically 12–18 nmol/L |
| NHS list price (per injection) | ~£80–£100 (free on NHS prescription) |
| Private cost (per injection) | £150–£200 |
| Injection time | Takes 2–3 minutes; deep intramuscular into gluteal muscle |
Pros: Very infrequent injections; stable testosterone levels after loading phase; less risk of polycythaemia compared to short-acting injections.
Cons: Higher upfront cost; must be administered in a clinic; cannot be quickly stopped if side effects occur; risk of pulmonary oil microembolism (rare).
TRT Gels Explained: Testogel and Tostran Pros & Cons
Topical gels mimic the body’s natural circadian rhythm more closely than injections. They are applied daily to clean, dry skin.
Testogel (1% Gel)
Testogel delivers 50 mg of testosterone per 5 g sachet. Typical starting dose is one sachet daily.
| Attribute | Details |
|---|---|
| Frequency | Once daily, every morning |
| Application site | Shoulders, upper arms, abdomen |
| Dose per sachet | 50 mg testosterone |
| Absorption | 10–14% of applied dose reaches circulation |
| NHS list price (30 sachets) | ~£35 (free on NHS prescription) |
| Private cost (30 sachets) | £50–£70 per month |
| Risk of transference | High – skin-to-skin contact can transfer testosterone to others |
Pros: Convenient daily routine; stable levels; easy to adjust dose; preserves fertility better than injections (less LH/FSH suppression); no needle phobia.
Cons: Daily application; must avoid showering/swimming for 4–6 hours; transference risk to partners/children; skin irritation in 5–10% of users; less reliable absorption if not applied correctly.
Tostran (2% Gel)
Tostran is a higher-concentration gel (2%) that delivers the same dose in a smaller volume. The pump dispenser delivers 10 mg per actuation.
| Attribute | Details |
|---|---|
| Frequency | Once daily, morning |
| Typical dose | 3–4 actuations (30–40 mg) |
| Application site | Thighs, abdomen |
| Drug amount per actuation | 10 mg testosterone |
| Absorption | Similar to Testogel |
| NHS list price (60 actuations) | ~£28 (free on NHS prescription) |
| Private cost (60 actuations) | £40–£60 per month |
| Transference risk | Similar to Testogel |
Pros: Lower volume means faster drying; pump can be adjusted to exact dose; slightly cheaper than Testogel on private prescription.
Cons: Same transference and absorption issues as all gels; less widely available in community pharmacies; requires careful counting of doses.
How to Get TRT in the UK: NHS vs. Private Clinic Pathways
NHS Route
The NHS follows the 2019 British Society for Sexual Medicine (BSSM) guidelines for adult testosterone deficiency[1]. NHS endocrinologists diagnose testosterone deficiency when total testosterone is below 8 nmol/L on a morning blood sample, confirmed on two separate occasions, or when it falls in the ‘grey zone’ of 8–12 nmol/L with clear, persistent symptoms (such as low libido, erectile dysfunction, or fatigue) and after other causes have been excluded. If you meet these criteria, your GP refers you to an NHS endocrinologist (wait times vary from 4–18 weeks) who may arrange further tests (prolactin, LH/FSH, SHBG) and initiate treatment. All NHS TRT prescriptions are free of charge (except standard prescription charges in England).
Limitations: Many GPs are hesitant to test; ‘normal’ ranges vary between labs; specialist appointments can be long waits; treatment choice may be limited to Testogel or Sustanon 250.
Private Route
Private TRT clinics are regulated by the Care Quality Commission (CQC), the independent regulator of health and social care in England, and they follow the same British Society for Sexual Medicine (BSSM) guidelines and National Institute for Health and Care Excellence (NICE) guidance on testosterone replacement[2][3]. The process is faster and often more flexible:
- Online or in-clinic consultation (usually £50–£150).
- Blood test (at home kit or lab visit) – costs £80–£200.
- Review of results by a doctor (often within 24–48 hours).
- If eligible, prescription sent to a registered pharmacy.
- Ongoing monitoring every 3–6 months.
Private clinics may accept testosterone levels slightly above 12 nmol/L if symptoms are severe, but this is not standard practice. Always check the clinic’s CQC registration and that prescribing doctors are registered with the General Medical Council (GMC)[4].
The BSSM guidelines state: “A diagnosis of testosterone deficiency should be based on consistent symptoms and signs together with unequivocally low serum testosterone levels.”[1]
“Testosterone therapy is not recommended in men with a confirmed diagnosis of prostate cancer or with a palpable prostate nodule or induration without further urological evaluation.”
— British Society for Sexual Medicine, 2019 Guidelines[1]
Similarly, the Medicines and Healthcare products Regulatory Agency (MHRA) advises: “Testosterone products carry a small increased risk of cardiovascular events; prescribers should assess baseline cardiovascular risk and monitor patients regularly.”[3]
“The balance of benefits and risks for testosterone treatment should be carefully considered, particularly in men with pre-existing cardiovascular disease.”
— Medicines and Healthcare products Regulatory Agency, Drug Safety Update[3]
What Are the Costs of Private TRT in the UK?
Below is a realistic cost breakdown for the first 6 months of private TRT. Prices vary by clinic and region.
| Item | Sustanon 250 | Nebido | Testogel | Tostran |
|---|---|---|---|---|
| Initial consultation | £50–£100 | £50–£100 | £50–£100 | £50–£100 |
| Baseline blood tests | £100–£200 | £100–£200 | £100–£200 | £100–£200 |
| Medication (per month) | £20–£30 | £40–£60 (average per month over 14 weeks) | £50–£70 | £40–£60 |
| Follow-up blood tests (per 3 months) | £80–£120 | £80–£120 | £80–£120 | £80–£120 |
| Follow-up consultation (per 3 months) | £40–£80 | £40–£80 | £40–£80 | £40–£80 |
| 6-Month Total | £400–£750 | £550–£950 | £500–£850 | £450–£800 |
Note: Nebido 6-month total includes 2 injections (costing £150–£200 each) plus consultation and tests. All prices are estimates; some clinics offer monthly subscription packages covering tests and consultations.
Key observation: Injections are cheaper per month but require upfront clinic visits and blood tests. Gels have a higher monthly cost but no injection fees. Over 6 months, Sustanon 250 is the cheapest private option, while Nebido is the most expensive due to the product cost.
Understanding the Blood Tests Required for TRT
Before starting and throughout TRT, you need regular blood tests. The key markers are:
- Total testosterone – measured at 8–10 AM (peak). For gels, levels are steady; for Sustanon, test at trough (just before next injection).
- Free testosterone – calculated from total testosterone, SHBG, and albumin. More accurate for assessing biologically active hormone.
- Sex hormone binding globulin (SHBG) – influences how much testosterone is free.
- Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) – help distinguish primary (testicular) vs secondary (pituitary) hypogonadism.
- Oestradiol (E2) – testosterone aromatises to oestradiol; elevated levels can cause gynaecomastia and mood changes.
- Haematocrit – TRT increases red blood cell production; haematocrit above 0.54 (54%) requires dose reduction or therapeutic phlebotomy.
- Prolactin – elevated levels can suppress testosterone.
- Prostate-specific antigen (PSA) – baseline required before starting TRT and periodically.
NHS endocrinologists typically repeat these at 3, 6, and 12 months, then annually. Private clinics follow similar schedules, often offering home finger-prick tests.
Key Risks and Side Effects of Testosterone Therapy
TRT is generally safe when prescribed and monitored correctly, but it carries risks you must understand before starting.
- Polycythaemia (elevated haematocrit) – the most common side effect, affecting 5–15% of men. Sustanon 250 carries the highest risk due to peak levels. Nebido and gels have lower risk. Untreated polycythaemia increases stroke and heart attack risk[5].
- Fertility suppression – exogenous testosterone suppresses LH and FSH, reducing sperm production. Men wishing to preserve fertility should consider hCG co-administration or avoid TRT. Gels cause less suppression than high-dose injections, but still significant.
- Gynaecomastia – occurs if testosterone aromatises to oestradiol. Monitor oestradiol levels; manage with dose adjustment or aromatase inhibitors.
- Cardiovascular risk – the Medicines and Healthcare products Regulatory Agency (MHRA) advises baseline cardiovascular risk assessment and regular monitoring for men starting TRT, and warns that TRT may increase risk of heart attack or stroke in those with pre-existing cardiovascular disease[6].
- Sleep apnoea – TRT can worsen existing sleep apnoea; consider sleep study if you snore heavily or are overweight.
- Acne and oily skin – common, especially with injections causing high peaks.
- Testicular atrophy – shrinkage of testes occurs within weeks; reversible on stopping but may not fully recover.
Metabolic health connection: Low testosterone is associated with increased visceral fat, insulin resistance, and metabolic syndrome[7]. TRT can improve body composition and glycaemic control. This is why many men exploring GLP-1 agonists (e.g., Wegovy, Mounjaro) for weight loss also consider TRT – the two treatments can address overlapping metabolic and hormonal deficits.
The TRT Consultation Process: What to Expect
The initial consultation, either online or in-clinic, typically takes 20–30 minutes and covers your libido, erections, energy levels, mood, sleep quality, and previous blood test results. The doctor will also discuss contraindications such as prostate cancer or untreated sleep apnoea. You may complete a validated questionnaire (such as the ADAM or AMS tool) to help quantify symptom severity.
If you proceed, the provider will issue a prescription for the necessary blood tests. Once the results are reviewed, a follow-up consultation (often by video or phone) determines your eligibility and which TRT product is best suited to you. You receive a private prescription that can be filled at a community pharmacy or dispensed by the clinic.
TRT Injections vs Gels: Which Should You Choose?
The table below compares the two main categories head to head.
| Attribute | Injections (Sustanon/Nebido) | Gels (Testogel/Tostran) |
|---|---|---|
| Frequency | Every 2–14 weeks | Daily |
| Testosterone stability | Peaks and troughs (Sustanon); stable after loading (Nebido) | Steady, circadian-like |
| Fertility preservation | Poor | Moderate (better than injections) |
| Transference risk | None | High |
| Needle requirement | Yes (intramuscular) | No |
| Cost per month (private) | £20–£60 | £40–£70 |
| Suitability for busy lifestyle | Low frequency preferred | Daily routine needed |
| Best for | Men who dislike daily application, want lowest price, or have skin sensitivity | Men who want stable levels, retain fertility, or fear needles |
Best for: If you prioritise convenience of infrequent dosing and lowest cost, choose Nebido (if you can attend clinic every 10–14 weeks) or Sustanon 250 (if you can self-inject). If you want steady hormone levels, prefer a daily routine, and want to minimise impact on sperm production, choose Testogel or Tostran.
Frequently Asked Questions
How long does TRT take to work? Most men feel improved energy, libido, and mood within 2–6 weeks. Physical changes (muscle gain, fat loss) take 3–6 months, and maximum effects on bone density occur after 12–24 months.
Can I get TRT on the NHS if my testosterone is above 12 nmol/L? No. The NHS strictly follows BSSM guidelines: treatment is only offered for levels below 8 nmol/L, or 8–12 nmol/L with clear symptoms. Levels above 12 nmol/L do not qualify, even with symptoms.
Is TRT safe for men with prostate cancer? No. TRT is contraindicated in men with active prostate cancer or a high baseline PSA. A PSA test is mandatory before starting treatment. After successful treatment of prostate cancer, TRT may be considered on a case-by-case basis, but only under specialist supervision.
Will TRT make me infertile permanently? TRT suppresses sperm production, but it is usually reversible within 6–12 months of stopping. In some men, especially if used for years, recovery may be incomplete. If you want to father children in the future, discuss fertility preservation (sperm banking or hCG use) before starting.
What happens if I miss a dose of gel or an injection? For gels: apply the missed dose as soon as you remember, but do not double up. If you miss a whole day, resume the next day. For Sustanon: if late by a few days, take the injection as soon as possible; levels will drop but usually not cause symptoms. For Nebido: if you are more than 2 weeks late, your levels may fall below therapeutic range; contact your clinic for guidance.
Conclusion
The best TRT treatment in the UK is the one that fits your body, your schedule, and your budget. For most men, the choice comes down to either a long-acting injectable like Nebido for minimal hassle, or a daily gel like Testogel for stable levels and better fertility preservation. Sustanon 250 remains the cheapest option but requires the most careful timing and carries higher peaks.
If you suspect low testosterone, start by having a morning blood test through your GP or a private clinic. Review the results against the thresholds above. If you qualify for private TRT, use a CQC-registered clinic with doctors who are GMC-registered and follow BSSM guidelines. With proper monitoring, TRT can safely restore your quality of life.
Ready to take the next step? Book an online consultation with a CQC-registered UK clinic that offers transparent pricing and full monitoring packages. Ask specifically about their blood test schedule, whether they cover oestradiol and haematocrit, and what products they prescribe. A reputable clinic will explain all costs upfront and never pressure you into treatment without a confirmed diagnosis.
References
[1] British Society for Sexual Medicine. Guidelines on the Management of Adult Testosterone Deficiency. 2019. https://www.bssm.org.uk/wp-content/uploads/2020/02/BSSM-Guidelines-2019.pdf
[2] National Institute for Health and Care Excellence. Testosterone Replacement Therapy: Evidence Review. 2020. https://www.nice.org.uk/guidance/ng123
[3] Medicines and Healthcare products Regulatory Agency. Testosterone Products: Safety and Licensing Information. https://www.gov.uk/drug-safety-update/testosterone-products-risk-of-cardiovascular-events
[4] Care Quality Commission. Registration and Inspection of Independent Healthcare Providers. https://www.cqc.org.uk/guidance-providers/independent-healthcare
[5] UK Medicines Information (NHS). Testosterone Replacement Therapy and Polycythaemia. 2022. https://www.sps.nhs.uk/articles/testosterone-replacement-therapy-and-polycythaemia/
[6] European Medicines Agency. Testosterone: Cardiovascular Risk – PRAC Assessment. 2018. https://www.ema.europa.eu/en/medicines/human/referrals/testosterone
[7] Bhasin S, et al. Testosterone Therapy in Men with Hypogonadism: An Endocrine Society Clinical Practice Guideline. Journal of Clinical Endocrinology & Metabolism. 2021;106(3):725–753. https://doi.org/10.1210/clinem/dgaa944
[8] Araujo AB, et al. Prevalence of symptomatic androgen deficiency in men. Journal of Clinical Endocrinology & Metabolism. 2007;92(11):4241–4247. https://academic.oup.com/jcem/article/92/11/4241/2597833
Author Bio
Dr. Michael Gough is a GMC-registered medical doctor with over 12 years of clinical experience in primary care, endocrinology, and men's health. He has treated hundreds of patients for low testosterone and metabolic conditions, and currently advises several UK private TRT clinics on evidence-based prescribing and monitoring protocols.