Skip to main content

Health condition

TRT decision guide

Testosterone replacement therapy (TRT) can transform symptoms of confirmed deficiency - but it is a long-term commitment with fertility implications, so the decision deserves proper specialist input.

Last reviewed 2026-09-27 · Next review due 2027-09-27

Key points

  • TRT is appropriate only when deficiency is confirmed on repeated morning blood tests with consistent symptoms

  • TRT suppresses sperm production - discuss fertility plans before starting

  • Options include gels, and short- or long-acting injections

  • Requires ongoing monitoring of testosterone, blood count and PSA

  • A urologist, andrologist or endocrinologist should oversee initiation and follow-up

Understanding it

About TRT decision guide.

TRT restores testosterone to normal levels via gels or injections, typically improving energy, libido, erections, mood and body composition in men with genuine deficiency. It is not a supplement for normal ageing, and starting it switches off the body's own production, including sperm.

Confirmatory testing, a fertility discussion (sperm banking or alternatives such as gonadotrophins where fatherhood is planned), and a monitored trial with scheduled blood tests. On the NHS, routine referrals of this kind often take 20-45+ weeks in many areas, whereas a private consultant urologist or andrologist can typically see you within around two weeks, with any tests and treatment arranged promptly afterwards.

A quiet reminder

This guide is for information, not medical advice.

Your GP or specialist knows your history and can tell you which parts apply to you. If in doubt, see them - and treat sudden severe symptoms as an emergency.

Frequently asked

Common questions about TRT decision guide.

Quick, plain-English answers to what people ask us most.

  • What is testosterone replacement therapy (TRT)?

    TRT is treatment with supplemental testosterone, given by injection, gel, patch or other methods, to restore normal testosterone levels in men diagnosed with clinically low testosterone (hypogonadism).

  • Who might need TRT?

    TRT is generally considered for men with symptoms of low testosterone, such as fatigue, low libido, reduced muscle mass or mood changes, combined with confirmed low blood testosterone levels on repeated testing.

  • What are the symptoms of low testosterone?

    Reduced libido, erectile difficulties, fatigue, low mood, reduced muscle mass and strength, and sometimes hot flushes or reduced body hair are common symptoms prompting testing.

  • Is TRT safe?

    TRT is generally safe when appropriately prescribed and monitored, but it carries some risks including effects on fertility, red blood cell count, and prostate health, so regular monitoring with a specialist is important.

  • Will TRT help if my testosterone level is normal?

    TRT is not recommended for men with normal testosterone levels and symptoms from another cause, as it won't address the underlying issue and carries unnecessary risk; accurate diagnosis with repeat blood testing is essential first.

  • How is TRT given?

    Options include intramuscular injections (every one to twelve weeks depending on formulation), daily gels or patches, and, in some cases, implanted pellets, with the choice depending on convenience, cost, and individual response.

  • How long does it take to feel the benefits of TRT?

    Some symptoms like libido and mood can improve within a few weeks, while effects on muscle mass and energy typically take a few months of consistent treatment to become apparent.

  • TRT vs lifestyle changes for low testosterone - what's the difference?

    Lifestyle changes such as weight loss, better sleep and exercise can meaningfully raise testosterone in some men, particularly those with obesity-related low levels, and are often tried or combined alongside TRT rather than as a strict alternative, guided by specialist advice.

  • Does TRT affect fertility?

    Yes, TRT commonly suppresses natural sperm production and can reduce fertility, so men wishing to conceive should discuss this carefully with a specialist before starting treatment, as alternative approaches may be more suitable.

  • When should I see a specialist about low testosterone, and how quickly can I be seen privately?

    See a specialist if you have persistent symptoms and confirmed low testosterone on repeat testing. NHS endocrinology waits can be lengthy; private endocrinologists or men's health specialists can often see you within about two weeks.