Testosterone replacement therapy explained

Testosterone replacement therapy (TRT) restores testosterone to a normal range in men diagnosed with testosterone deficiency. It is prescription-only in the UK, lifelong in nature (levels fall back once stopped), and delivered through injections, gels, capsules or clinic-administered long-acting preparations.

Who it is for

Men with symptoms plus two morning blood tests showing low total testosterone (assessment threshold: below 12 nmol/L BSSM-aligned; many NHS labs use 8–12). TRT is not a "vitality optimisation" product for men with normal testosterone — the UK press scrutiny (BBC, Pharmaceutical Journal) centres on exactly that misuse.

What it fixes — and what it doesn't

Published benefits concentrate in: libido and erectile function, energy and mood, muscle mass with training, bone density. It is not a cure for depression, not a substitute for sleep, and not a weight-loss drug — trials show modest effects, and symptom relief varies between men.

The forms (see forms guide)

Injections 1–3×/week (most common); daily gels; oral capsules 2×/day; long-acting clinic injections.

The commitment

Lifelong monitoring (haematocrit, PSA — see risks), fertility suppression unless mitigated (fertility guide), and twelve_month all-in costs of £720–£2,300 privately (costs) vs NHS prescription charges.

The UK provider landscape

Our directory lists twelve clinics with verified facts — CQC status, named doctors, published prices. The market splits into national telehealth (Optimale, Manual, Numan), hybrid clinic+online (Balance My Hormones, Origin TRT), and traditional clinics (Centre for Men's Health, WellMan Clinic — Harley Street lineage).

Sources: BSSM-aligned publications, TRAVERSE trial reporting, clinic published pages verified 2026-10-08. Not medical advice.

Affiliate disclosure: Some pages contain affiliate or advertising links, marked with 'sponsored'. Listings are never sold ranking — featured status is labelled on the page. Clinic data is published free regardless of commercial relationships.

Information directory — medically reviewed sources cited per page · Source-checked 2026-10-09 · Independent information directory — not medical advice.