Testosterone replacement: who it is for and who it is not

A treatment with a clear indication and a blurred market

Testosterone replacement works for men who have hypogonadism. The diagnosis, and what it requires, is covered separately on this site. This page is about what follows a confirmed diagnosis — and about who should not be treated.

Nothing here is a recommendation. It is what the guidelines say and what a careful prescriber does.

Who it is for

Men with symptoms and signs of testosterone deficiency, confirmed by two low morning fasting measurements on separate days, with LH and FSH measured to establish the cause, and with reversible causes addressed first.

That last clause carries most of the weight. Obesity, obstructive sleep apnoea, opioid use, significant alcohol intake, acute illness and severe stress all lower testosterone. Treating those can raise it without any hormone being prescribed, and a work‑up that skips them will reliably conclude that hormone treatment is needed.

Who it is not for

Guidelines are explicit, and these are the categories where treatment is contraindicated or requires specific caution:

• Men who want to father a child in the foreseeable future. Exogenous testosterone suppresses the body's own production and with it sperm production, sometimes substantially and sometimes slow to recover. This must be discussed before the first dose, not after.
• Untreated severe sleep apnoea. Treatment can worsen it.
• Known or suspected prostate or breast cancer.
• Raised haematocrit at baseline, since treatment raises it further.
• Unevaluated prostate symptoms, or a PSA that needs assessment first.
• Recent major cardiovascular event — several guidelines advise deferring.
• Men whose results are normal. "Not optimal" is a marketing category, not a diagnosis.

What monitoring actually involves

This is the part that distinguishes treatment from a transaction. A prescription without a monitoring schedule is incomplete:

• Haematocrit at baseline and periodically. A rise above threshold means reducing the dose, stopping, or in some cases venesection.
• Testosterone levels, timed according to the preparation used, since what counts as a correctly timed sample differs between injections, gels and pellets.
• PSA in men over the relevant age, at baseline and during treatment.
• Symptoms, because the point is how the man feels, not the number.
• Blood pressure, and lipids where indicated.

What the cardiovascular evidence now says

This question was unsettled for years. The TRAVERSE trial, in men with hypogonadism and cardiovascular risk, did not find an excess of major adverse cardiac events with treatment. It did report higher rates of atrial fibrillation, acute kidney injury and pulmonary embolism.

The fair reading is reassuring on the main question, with signals that warrant monitoring. A clinic describing it as "proven safe" has rounded a nuanced result in its own favour.

What it does and does not deliver

In men who are genuinely deficient, treatment reliably improves sexual function, and improves lean mass and bone density. Effects on mood and energy are reported but more variable.

What it is not: a weight‑loss treatment, a performance enhancer for men with normal levels, or an anti‑ageing intervention. The evidence does not support any of those three, and all three are sold.

The preparations, briefly

Injections, gels and long‑acting depot formulations all exist, and at least one long‑acting injectable is registered in Costa Rica for male hypogonadism. They differ in how stable the levels are, how often they are given, and in practical issues — gels can transfer to a partner or child by skin contact, which needs explaining.

Which preparation suits someone is a clinical choice. Availability here changes, and the registry rather than a clinic's website is where to check what is registered.

The boundary

Men who genuinely have hypogonadism are also under‑diagnosed, and this page is not an argument against treating them. It is an argument that the sequence matters: symptoms, two correctly drawn samples, the panel around them, reversible causes addressed, fertility discussed, and a monitoring plan agreed — before the first prescription.