What do you think of when you hear “high testosterone?” Macho men? Aggressive behaviour? An extra strong sex drive or above-par athleticism?

Well, naturally-occurring testosterone excess is actually pretty rare in men. So it’s unlikely to be the cause behind any of those things. But testosterone is an important hormone, playing a key role in your body’s systems and functions—and if the balance is off, it’s something to address.

Key Takeaways

• High testosterone in men is rare, and the level considered high depends on your age and the lab’s reference range.
• High testosterone in men is hard to spot, but signs may include acne, hair loss, increased sex drive, weight gain, high blood pressure or fertility issues.
• Most cases are caused by steroid or hormone therapy rather than an underlying medical condition. But possible medical causes include tumours or genetic conditions.
• Too much testosterone can raise the risk of blood clots, strokes and heart attacks. It can also impact fertility.
• If you are on testosterone replacement therapy (TRT), you will have regular check-ins and monitoring with your doctor to ensure your levels stay within a safe range.

What counts as a high testosterone level in men?

High testosterone—also known as hypergonadism or hyperandrogenism—is when your testicles overproduce the hormone testosterone.

Since high testosterone in men is rare, diagnostic ranges aren’t very well defined. A general normal range for a man aged 18 to 39 years old is around 9.15 to 31.8 nmol/L (264 to 916 ng/dL) (that’s nanograms of the hormone per deciliter of your blood).

But “normal ranges” for testosterone levels also vary based on the type of blood test done and the lab where it’s done.

In men, testosterone levels naturally decrease slightly with age, too, so the testosterone level considered high also decreases.

Signs of high testosterone in adult men

High testosterone is easier to spot in boys, as it can lead to early puberty. In adult men, it’s more difficult to identify. But signs of high testosterone can span several aspects of your health and body.

Sexual and reproductive

• Increased sex drive
• Fertility problems

Skin, hair and body

• Acne
• Early baldness
• Excessive body hair
• Unexplained weight gain
• Changes in body odour

Heart and blood-related

• High blood pressure
• Fluid retention and swelling in your legs and feet

Sleep and mood

• Insomnia
• Mood swings

It’s important to bear in mind, though, that all of these issues can have many causes that aren’t excess testosterone. That’s why it’s a good idea to reach out to a healthcare provider, who can give you a blood test.

If you have high testosterone for medical reasons (more on what those could be below), it usually comes with changes in other hormone levels. So that can be a tell-tale sign for your doctor.

For example, if someone has a tumour that leads to extra testosterone, it often causes the brain’s hormone signals to drop. This tells doctors that something unusual is going on and needs more testing.

Men often associate aggression with having high, or excessive, testosterone levels. But if testosterone was to be a factor in temperament, it would be really subtle. It’s more likely that stress, and the ways men are socialised, are the culprits of aggression.

If you think you may be noticing signs of high testosterone, talk to your healthcare provider. They can do some testosterone levels tests or send you to a specialist.

What causes high testosterone?

Causes of high testosterone in males come down to several factors, including:

• Tumors in the testicles that make too much testosterone (for example, Leydig cell tumors in the testes, which can be harmless or cancerous).
• Problems with the adrenal glands, like tumours or a genetic condition called congenital adrenal hyperplasia (CAH), where the body makes too much of certain hormones.
• Early puberty, caused by the brain sending signals to start hormone production too soon.
• Taking testosterone from outside the body (like steroids or hormone therapy).

It’s worth reiterating that high testosterone from natural or medical causes is rare. Most of what we see of abnormally high testosterone levels comes down to steroid or hormone use.

And for the record, lifestyle factors— like sleep, diet, or stress—are not linked to excess testosterone.

Side effects of high testosterone

You might wonder what happens to a man when his testosterone is too high.

High testosterone levels can cause the body to make more red blood cells. This makes the blood thicker and stickier, which can raise blood pressure, meaning side effects of high testosterone can include:

• Blood clots
• Strokes
• Heart attacks

When high testosterone levels cause the brain’s hormone signals (FSH and LH) to drop, it can also lead to lower fertility and make it harder to have children.

But to put the aggression myth to bed once more—research has shown that even when men with normal levels of natural testosterone were given very high doses of testosterone, it didn’t make them more aggressive or angry.

If you’re on a TRT plan, you’ll have regular monitoring and check-ins with your clinician to ensure your testosterone levels are continuously kept in a healthy range.

How to safely treat and reduce high testosterone in men

The first step in lowering high testosterone in men is to stop using anything that could be increasing it. This includes anabolic steroids (AAS), certain peptides, and supplements that might be contaminated with steroids.

Doctors then check how the brain and hormone system (the pituitary gland) are working.

• If the hormones FSH and LH levels are low, it could mean something in the body—like a tumour—is making extra testosterone, so a full-body CT scan may be needed.
• If FSH and LH levels are high, it means the brain is sending the wrong signals, and you may need to see a hormone specialist (AKA an endocrinologist) for further tests.

If the cause of the high testosterone is organic (i.e., not brought on by steroids or hormone therapy), then you’ll need to be treated for the underlying condition in order to bring your testosterone levels down.