If you’re over 45 and have been feeling off lately: you might have low testosterone.

About 4 to 5 million men in the United States do. Only about 5% of them are getting treatment for it. Which means there are a lot of guys out there running on fumes, thinking this is just what getting older feels like, when in fact there’s a well-studied, medically supervised treatment that could help.

What Is TRT (and Who Is It For)?

Let’s be clear: TRT is not steroids for guys who want bigger arms. It’s not simply a performance enhancer.

What it is: a medically supervised treatment that restores your testosterone to normal levels when your body has stopped producing enough on its own. Think of it less like upgrading your engine and more like putting the correct grade of oil back in it. Your car was designed to run on this stuff. Without it, things get clunky.

Signs of Low Testosterone

Low testosterone is sneaky. It doesn’t arrive with a banner and a trumpet. It shows up gradually, like a guest who keeps dimming the lights at your party until suddenly you’re all sitting in the dark wondering what happened to the vibe.

The most common signs include:

A lot of men chalk this up to stress, or age, or the general condition of being alive in the modern era. And sometimes those things are the cause. But sometimes they’re masking a hormonal deficiency that’s entirely treatable. The only way to know is to get tested.

Normal Testosterone Levels by Age

Your testosterone peaks sometime in your late teens to early twenties, back when you had opinions about everything and the energy to argue about them, and then declines about 1% per year after 30. Here’s a rough reference range for total testosterone:

These ranges vary by lab. What matters clinically is where your number sits relative to how you feel. A guy at 310 with zero symptoms is in a very different situation than a guy at 310 who can barely get through his afternoon without a nap and a small existential crisis.

What Causes Low Testosterone?

The causes break into two camps, and the distinction matters because it changes how your doctor approaches treatment.

Primary Hypogonadism

This means the problem is in the testes themselves. The brain is sending the signal, “Hey, make testosterone”, but the factory is struggling. Causes include testicular injury, infections like mumps orchitis, chemotherapy, radiation, or genetic conditions like Klinefelter syndrome.

Secondary Hypogonadism

Here the factory is fine, but the management office (the hypothalamus and pituitary gland in the brain) isn’t sending the right orders. This can result from obesity, type 2 diabetes, chronic opioid use, pituitary tumors, head injuries, or, and this is a common one, prolonged use of anabolic steroids, which essentially teaches your brain to stop asking for natural production.

And then there are the lifestyle factors, which are both the most common and the most fixable: chronic stress, poor sleep, heavy drinking, and sitting around all day. In a lot of cases, low T is some combination of natural age-related decline plus these contributing factors stacking up over time. Which is why a good diagnostic workup is essential before anyone hands you a prescription.

How to Get Tested and Diagnosed

This is the part where you actually do something instead of just reading about it on your phone at 11 PM, so pay attention.

The Blood Panel

A responsible provider won’t just check your total testosterone and call it a day. You need a comprehensive hormone panel, which includes total testosterone, free testosterone (this is the stuff your body can actually use, total T includes testosterone that’s bound up and unavailable, like money in a retirement account you can’t touch), sex hormone-binding globulin (SHBG), LH and FSH (these tell your doctor whether the problem is in your brain or your testes), a complete blood count to establish your baseline hematocrit (this becomes important later), a metabolic panel, a lipid panel, PSA if you’re over 40, and estradiol.

That’s a lot of acronyms. The point is: your doctor needs the full picture, not just a single data point.

The Rules of Testing

How to Get a TRT Prescription

Alright, so your labs came back low. Twice. Your symptoms check out. Now what?

The In-Person Route

Urologists and endocrinologists are the specialists best equipped to manage TRT. Your primary care doctor can also prescribe it, though specialists tend to be more fluent in the nuances of dosing, monitoring, and the inevitable adjustments that come with dialing things in. The key thing to look for in any provider: do they monitor you after prescribing? A doctor who writes a script and sends you on your way is a doctor doing half the job.

The Telehealth Route

Online men’s health clinics have made TRT much more accessible, which is mostly good but also means you need to be discerning. The best ones handle lab orders, virtual consultations, prescriptions, and medication delivery in a streamlined package. The worst ones are basically prescription mills in a nice website’s clothing.

Your First Visit

Whether you walk into an office or open a laptop, the first appointment should involve a thorough review of your symptoms, your medical history, your current medications, and your lab results. The provider should explain the different treatment options, walk through the risks and side effects without either minimizing or catastrophizing them, and set up a monitoring schedule. If any of that gets skipped, you’re at the wrong place.

How TRT Works: Methods, Dosing, and What to Expect

Now we get into the practical stuff. There are several ways to get testosterone into your body, and the best method depends on your lifestyle, your tolerance for needles, and how your body responds.

Administration Methods

Intramuscular injections of testosterone cypionate remain the most commonly prescribed method, mostly because they’re cheap, effective, and backed by decades of data. They’re the Toyota Camry of TRT delivery methods: not glamorous, totally reliable.

Typical Dosing

Most guys start on 100 to 200 mg of testosterone cypionate or enanthate per week, often split into two smaller injections (say, 80 mg Monday and 80 mg Thursday) rather than one big dose. Splitting the dose keeps your blood levels more stable, which means fewer side effects and less of that roller-coaster feeling where you feel great for three days and then like a wet blanket for four. Your provider will adjust based on follow-up labs, usually at the 6-week and 12-week marks.

When Will You Notice a Difference?

TRT is not a light switch. It’s more like a sunrise. Research published in the New England Journal of Medicine found: mood improvements tend to show up within 3 to 4 weeks, subtle at first, like you suddenly realize you didn’t need that third cup of coffee. Libido and sexual function typically improve within 3 to 6 weeks. Body composition changes, more muscle, less belly, take 3 to 6 months. Full bone density benefits take a year or two.

The timeline depends on where you started, how consistent you are, and what else you’re doing (diet, exercise, sleep). TRT is not a substitute for those things. It’s the foundation that makes those things possible again.

Medical Oversight and Monitoring

This section is important and also, I’ll be honest, not the sexiest part of the guide. But it’s the part that separates responsible TRT from the kind of thing you look back on in five years and wince about.

The Follow-Up Schedule

After starting TRT, you need blood work at 6 weeks (to check your initial response), at 3 months (for dose optimization), and then every 6 to 12 months for as long as you’re on therapy.

Side Effects and What to Do About Them

Most TRT side effects are dose-dependent, meaning they’re usually fixable by adjusting the dose.

None of this is unmanageable. But all of it requires monitoring.

What Does TRT Cost?

Let’s talk money, because this is always the question people are afraid to ask, so they just don’t, and then they’re surprised.

The most affordable route is generic testosterone cypionate picked up at your pharmacy with a GoodRx coupon. We’re talking under $30 for a vial that lasts two months. This is not an expensive medication. The expensive parts, if there are any, tend to be the telehealth subscriptions or the fancy delivery methods.

Insurance Coverage

Many insurance plans cover TRT if you have a documented diagnosis of hypogonadism, meaning two blood tests confirming low testosterone plus clinical symptoms. That said, coverage varies wildly, so call your insurer and ask about formulary status for your specific medication, whether prior authorization is required, whether they cover monitoring labs, and whether they require step therapy (i.e., making you try the cheapest option before approving something else). Even with insurance, injectable testosterone is typically a low-cost generic, so your out-of-pocket is usually pretty modest.

Benefits, Risks, and the Bottom Line

What TRT Can Do For You

When administered properly and monitored responsibly, TRT has been shown to improve energy levels and reduce that soul-crushing fatigue, restore a healthy sex drive and erectile function, increase lean muscle mass while reducing body fat, sharpen mood, motivation, and cognitive clarity, support bone mineral density, and improve certain markers of cardiovascular health (though the long-term cardiovascular picture is still being studied).

That’s a meaningful list. For a lot of men, TRT is the difference between going through the motions and actually being present in their own lives.

Who Should Not Do This

One piece of good news on the risk front: the TRAVERSE trial, published in the New England Journal of Medicine in 2023 and one of the largest randomized controlled studies on TRT, found that testosterone therapy did not increase the risk of major cardiovascular events in men with hypogonadism who had preexisting cardiovascular risk. This was a significant finding that has meaningfully reshaped the risk-benefit conversation around TRT.

The Takeaway

TRT is a legitimate, evidence-based medical treatment for men with clinically confirmed low testosterone. It’s not a miracle, and it’s not a shortcut. It’s a correction: a way of giving your body back what it’s no longer making enough of on its own.

Getting properly diagnosed requires fasting morning blood work, done twice. Multiple delivery methods exist, with injectable testosterone cypionate being the most cost-effective and well-studied. Ongoing monitoring is essential. Costs are manageable. Both telehealth and in-person providers can prescribe TRT, but the quality of care varies enormously, so choose someone who treats follow-up labs as non-negotiable, not optional.

If any of this resonated, if you’ve been feeling off and you can’t quite put your finger on why, the first step is simple and costs you nothing but an early morning and a blood draw. Get your levels tested. Have the conversation. You’ve been running on whatever version of yourself this is for long enough. It’s worth finding out whether there’s a better one available.