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Some men shouldn't be on testosterone.
Most clinics won't tell you that, because they make money when you start. Here are five reasons Peter will say no — and the reasoning behind each one, so you can judge for yourself.
My job is not to sell you testosterone. My job is to teach you about it, so we can do what's safe, ethical and medically right.
Peter O'Brien, NP1. You want children soon
This is the one that catches people out. When testosterone levels in your brain go high enough, your brain stops telling your testes to produce sperm. It isn't a side effect — it's the system working the way it's built.
If you're trying for a child, or expect to be in the next year or two, testosterone will lower your chances. There are other routes for men in that situation. Say so before you start, not after.
2. You have active or untreated prostate cancer
Worth being precise here, because the internet is not. Testosterone does not cause prostate cancer. That myth has been around for decades and it isn't supported.
But if you already have prostate cancer and it's active or untreated, you shouldn't start testosterone while that's the case. It's one of the reasons PSA is on every lab panel we run — baseline and then ongoing.
3. You have sleep apnoea that isn't under control
Low oxygen overnight is hard on your heart, your blood pressure and your general health before testosterone enters the picture. Testosterone also thickens the blood slightly, which doesn't help.
If any of this sounds like you, get screened before you start:
- You snore loudly
- You wake up gasping
- You're exhausted even after a full night's sleep
Treated apnoea isn't a barrier. Untreated apnoea is a reason to wait.
4. You have uncontrolled heart failure
Men with heart failure need clearance from their cardiologist before starting testosterone. Not from us — from the specialist who knows their heart.
The honest state of the evidence: there are a lot of studies on testosterone and heart failure, and when researchers pooled them together in a meta-analysis, the result came back inconclusive. That's the real answer, and it's why we defer to your cardiologist rather than guessing.
5. You're not doing proper labs
This is the one that turns a safe treatment into a dangerous one, and it's entirely avoidable.
No responsible clinic should ever give you testosterone without a proper set of labs. Baseline before you start. Follow-up labs after. Tracking how you're actually feeling. Proper dosing. Ongoing blood monitoring.
If a clinic will prescribe after a form and a credit card, that tells you what you need to know about how closely they'll be watching once you're a customer.
Testosterone is extremely safe when it's done correctly. It can be dangerous when it's done recklessly.
Peter O'Brien, NPWhat we watch, and why
- PSA — prostate
- Hematocrit and hemoglobin — blood thickness
- Estrogen — balance
- Total and free testosterone — are we actually there yet
- Liver enzymes
If none of this applies to you
Then testosterone may well be worth a conversation. It starts with bloodwork, not with a prescription, and if the numbers don't support treatment we'll tell you that too.
My job is to optimise your health safely, not rush you into something that isn't right.
Start with a conversation. If it isn't a fit, that's a useful answer too.