Testosterone

Testosterone is the most over-prescribed hormone in American medicine right now, and it’s not close. Walk into a strip-mall “low T clinic” with a pulse and a complaint about being tired, and you’ll walk out with a prescription for testosterone cypionate and a follow-up appointment to buy more of it. Nobody drew labs at 7 AM fasting. Nobody asked about your sleep. Nobody checked whether you snore loud enough to wake your wife. The business model requires that you start the medication and keep paying for it, and the business model is very good at what it does.

The actual clinical question is narrower than the marketing suggests. Some men genuinely have hypogonadism and benefit a lot from replacement. Most men who walk into those clinics don’t, and the thing making them feel like garbage is something testosterone won’t touch.

I’ll spend this post on the difference, because the difference matters and almost nobody who’s selling TRT is going to draw it for you.

What a real low-T diagnosis looks like

The Endocrine Society guideline is not subtle about this. You need two separate morning total testosterone levels, drawn fasting before 10 AM, both below 300 ng/dL. You need symptoms of hypogonadism, which means specific things: low libido, erectile dysfunction, loss of morning erections, loss of body hair, gynecomastia, decreased muscle mass, decreased bone density. Not “I’m tired.” Not “I don’t feel like myself.” Tired is not a hypogonadal symptom. Tired is what happens when you’re a 47-year-old man in 2026.

The labs have to be morning-drawn and fasting because testosterone has a circadian rhythm. A guy who’s 450 ng/dL at 8 AM is going to be 280 ng/dL at 4 PM, and the 4 PM number means nothing. Afternoon draws are one of the most common ways men get falsely diagnosed. The clinic gets a low number, calls it pathology, starts the injections. The number was never pathological in the first place.

Once you do have two confirmed low morning levels, the next step is figuring out why. You check LH and FSH. High LH with low T means primary hypogonadism (testicular failure). Low or normal LH with low T means secondary hypogonadism (pituitary or hypothalamic). You check prolactin, you check iron studies for hemochromatosis, you image the pituitary if there’s a reason. None of this happens at a low-T clinic. The clinic doesn’t care which kind you have. They sell the same thing to both.

The four things that mimic low T

Here’s what actually causes the symptoms most men show up with, in rough order of how often I see it:

Sleep apnea. A 50-year-old man with a 17-inch neck and a snoring problem will have low energy, low libido, brain fog, weight gain, and yes, suppressed testosterone, because apnea suppresses the HPG axis. Treat the apnea and the T comes up on its own about a third of the time. Start him on TRT instead and you’ll make his apnea worse, because exogenous testosterone is independently associated with worsened OSA. This is the single biggest miss in the whole industry.

Depression. Major depression suppresses libido, motivation, energy, and yes, often testosterone. The symptom overlap with hypogonadism is nearly total. A guy comes in saying he has no drive and no interest in sex and feels like he’s underwater, and the question is whether that’s a hormonal issue or whether he’s been clinically depressed for three years and never told anyone. SSRIs help the second guy. Cypionate does nothing for him.

Alcohol. Two or three drinks a night, every night, for a decade. Alcohol suppresses testosterone production directly and ruins sleep architecture indirectly. I’ve watched men’s testosterone come up 200 points after they quit drinking, with zero other intervention. Nobody at the TRT clinic asked how much they were drinking.

Deconditioning and weight gain. Adipose tissue aromatizes testosterone into estradiol. A 40-pound gain over the last five years will pull total T down meaningfully. Testosterone won’t fix that. Losing the 40 pounds will.

If you haven’t ruled out sleep apnea, alcohol, depression, and weight before starting TRT, you haven’t ruled out anything.

The patient who actually had it

I had a guy a couple years back, mid-30s, primary care had been telling him for two years his fatigue was just stress. He came to me thinking he was depressed. He wasn’t depressed. He was hypogonadal. Morning totals of 180 and 195, both fasting, drawn a month apart. LH was inappropriately low-normal, which pointed at secondary hypogonadism. Pituitary MRI showed a small prolactinoma. We treated the prolactinoma with cabergoline. His testosterone came back up to the high 400s on its own within four months, and the fatigue and libido issues resolved with it. He never needed exogenous testosterone. The clinic that would’ve started him on cypionate would’ve masked the prolactinoma for years.

That’s the point of doing the workup. Not gatekeeping. Catching the brain tumor before it gets big enough to compress the optic chiasm.

If you actually need it: the real side-effect picture

Assume you’ve been worked up properly and you have real, confirmed hypogonadism. TRT is a real treatment and it works. It also has real side effects that the bro-science scene mostly downplays.

The fertility piece is the one younger men keep getting blindsided by. A 32-year-old who hasn’t had kids yet, started on TRT at a clinic that never had the conversation, sperm count gone within a year, now sitting in a fertility workup wondering what happened. If you’re under 40 and you might want kids, your options are hCG monotherapy, clomiphene, or banking sperm before you start. The clinic that didn’t bring this up failed you.

The prostate question is more nuanced than it used to be. The old fear was that testosterone would feed prostate cancer. The data over the last fifteen years hasn’t really borne that out for men without active cancer, but you still check a baseline PSA in men over 40, you still do a digital rectal exam if it’s indicated, and you recheck PSA periodically. If a man already has prostate cancer, that’s a separate conversation with urology.

Monitoring schedule, the boring version: baseline labs (total T, free T, LH, FSH, prolactin, CBC, PSA if over 40, lipid panel, metabolic panel, hematocrit). At 3 months, recheck T and CBC. At 6 months, full panel again. Then yearly forever. Sleep study if there’s any snoring history or if hematocrit starts trending up. A prescriber who’s not doing this isn’t actually managing the treatment. They’re refilling a script.

The “I just want to feel better” patient

The most common version of this story is the guy in his late 40s who comes in saying he doesn’t feel like himself anymore. He’s tired in the afternoons, his marriage is in a rough patch, he’s gained 25 pounds, he’s not sleeping well, and a friend at the gym told him to get his T checked. He’s read enough internet to be hopeful low T is the answer.

Sometimes it is. More often he has poor sleep, too much alcohol, a depression he hasn’t named, a marriage problem he’s avoiding, and a body that hasn’t moved meaningfully in a decade. Testosterone, even if his number is borderline, doesn’t fix any of that. It gives him about six weeks of feeling sharper, which is mostly the placebo of having done something, and then he’s back to baseline still avoiding the actual problems, except now he’s on a medication he might be on for life and growing breast tissue.

Most men in their 40s and 50s who feel like garbage feel like garbage for reasons testosterone can’t touch. A real workup tells you which one you’re dealing with. A clinic that hands out cypionate without one is selling a feeling for the price of a treatment.