Does TRT cause hair loss?
It can, in men who are already prone to it. TRT hair loss is usually male pattern hair loss: thinning at the temples, the crown or both. Testosterone labels list it as a reported side effect.
The bigger driver is your genes. A medical textbook chapter on the topic says normal hormone levels are enough to cause hair loss in men who are genetically prone. So TRT may speed up a process your genes already started.
That is an educated guess, not a trial result. No study has measured hair loss in men treated for low testosterone. For the full list of side effects, see our guide to TRT side effects.
What is male pattern hair loss?
It’s the most common kind of hair loss in men. Doctors call it androgenetic alopecia, which means hair loss driven by genes and male hormones.
Here is how it works. An enzyme in the body turns some testosterone into DHT, a stronger hormone. DHT acts on hair roots on the scalp, and over time those roots shrink.
MedlinePlus, from the National Library of Medicine, says this shortens the growing phase of each hair. The hairs that grow back are shorter and thinner, until some roots stop making visible hair.
It’s very common. The Endotext chapter says it affects 30% to 50% of men by age 50. Other sources give higher numbers because they count it differently.
Genes explain most of the risk. The same chapter says heredity accounts for about 80% of who is prone to it.
MedlinePlus puts it in plain terms. It estimates that about 50 million men in the US have this kind of hair loss. It also says about 80% of men show some sign of it during their lives.
So many men on TRT would lose some hair with or without treatment. That makes it hard to tell what TRT added.
What do testosterone labels say about hair loss?
They list it, mostly without a number. Here is what we found.
| Label | What it says about hair loss |
|---|---|
| DEPO-Testosterone (cypionate injection) | Lists male pattern baldness among reactions seen with some male hormones, with no rate |
| Generic enanthate injection | Lists male pattern baldness, with no rate |
| Azmiro (cypionate injection) | Lists male pattern baldness, with no rate |
| AndroGel 1% (gel) | The only rate we found: about 1% of men in a 180-day trial |
| AndroGel 1.62%, AVEED | List hair loss among reports after approval, with no rate |
Reports made after a drug is approved come from a group of unknown size. The AndroGel 1% label says that means their frequency and cause can’t be reliably judged.
So the labels tell you hair loss can happen. They don’t tell you how often.
The labels also say testosterone builds male hair on the face and body. Hair can grow in some places and thin in others at the same time.
What do studies show about testosterone and hair loss?
The only studies we found with hair results are in transgender men starting testosterone. They are a different group from men treated for low testosterone, so read these as clues, not answers.
- The first year: a study followed 20 transgender men for a year after starting testosterone. Only one developed mild hair loss at the temples.
- The long run: the same team looked at 50 transgender men who had been on testosterone for about ten years. About a third had mild hair loss at the temples, and about a third had moderate to severe male pattern hair loss.
- Compared with other men: a large health-records study found hair loss was 2.5 times as common as in women not on testosterone. Compared with men not on testosterone, the difference was small and could have been chance.
A 2023 review of the evidence put it this way. Testosterone may bring on male pattern hair loss or speed it up, and it increases facial and body hair. The review noted that few studies measured hair carefully.
Your genes decide most of what happens to your hair, not the number on your lab report.
When does hair loss start on TRT?
We don’t know for men on TRT for low testosterone. No study has followed them for hair changes.
Guidelines for transgender men give a rough timeline. They say scalp hair loss on testosterone can start at 6 to 12 months and keep building for more than five years. In the one-year study above, only one of 20 men had any hair loss in the first year.
That fits how male pattern hair loss works. It is slow, and it usually takes months or years to notice. The AAD lists the early signs as noticeable thinning, a receding hairline, or balding.
If your hair starts falling out in clumps within weeks, that’s a different pattern. See the warning signs below.
Does the form of TRT make a difference?
We found no study comparing hair loss on injections, gels or other forms. The labels don’t help either: only one gel label gives a rate, and the others give none.
So there’s no good reason to switch forms for your hair. If you’re curious, ask your prescriber, who knows the trade-offs for you.
Does a higher testosterone level mean more hair loss?
Not in the data we found. In the study of transgender men, hair results did not track each person’s blood testosterone or DHT level.
That fits with what the Endotext chapter says. Normal hormone levels are already enough to cause hair loss in men who are prone to it. A higher level isn’t required.
One label adds a small piece. On weekly Xyosted shots, the ratio of DHT to testosterone stayed in the normal range at week 12.
So hair loss is a poor reason to chase a lower number. If you’re worried, talk it through with your prescriber, and don’t change your dose on your own.
Will TRT make body and facial hair grow?
Often, yes. This is an expected effect of testosterone, not a side effect. Labels say testosterone and DHT build and keep male hair on the face, chest, armpits and groin.
Low testosterone can do the opposite. The Endocrine Society names loss of body hair as one of the more specific signs of low testosterone. Our guide to low testosterone symptoms covers the others.
In the one-year study of transgender men, facial and body hair rose steadily. Transgender health guidelines say these changes start at 6 to 12 months and can keep building for more than five years. It’s possible to grow more beard while your hairline recedes.
Is it TRT, or something else?
Not all hair loss is male pattern hair loss. Some kinds have other causes that need a doctor. MedlinePlus says to contact a provider if:
- You’re losing hair in an unusual pattern, not the temples or crown.
- It’s happening fast, or you’re in your teens or twenties.
- Your scalp hurts or itches, or looks red or scaly.
The American Academy of Dermatology (AAD) adds a few more signs:
- A bald patch or strip that appears within a day or two.
- Round or oval bald patches on the scalp or in the beard. These can be a sign of alopecia areata, an immune condition.
- Shedding in clumps a few months after an illness, surgery, high fever or fast weight loss. Shedding 50 to 100 hairs a day is normal, the AAD says.
A dermatologist may order blood tests or take a small scalp sample to look for other causes. These can include thyroid problems, low iron or an infection.
Can you stop hair loss on TRT?
You can slow it, but not with anything we can recommend here. Treatment is a decision for you, your prescriber and a dermatologist.
The Endotext chapter says approved medicines can prevent more loss, but they only partly regrow hair. They work only while you keep using them.
If you’re thinking about any hair-loss medicine, ask your prescriber first. That includes ones sold online. Some of these medicines can lower PSA, a prostate blood test men on TRT have checked. Your prescriber needs to know so they read your PSA results correctly.
Some also list effects on sex drive, fertility or mood on their labels. If you ever have thoughts of harming yourself, call or text 988 in the US.
A dermatologist will ask about your health and your other medicines before suggesting anything. Make sure they know you’re on testosterone.
Will your hair grow back if you stop TRT?
Probably not, and stopping is not a decision to make alone. The Endotext chapter says that once hair roots have shrunk far enough, the loss is likely permanent.
Transgender health guidelines say the same about testosterone in that group. They list male pattern baldness among the changes that last after stopping hormones.
Stopping TRT would also bring back the symptoms you started it for. If hair loss bothers you, see a dermatologist early, while there is more hair to keep.
How can you track hair changes on TRT?
Hair loss is slow, so it’s easy to miss or to imagine. Photos help more than the mirror.
- Take the same photos of your hairline, temples and crown every two to three months. Use the same light, angle and distance.
- Write down the date you started TRT and any change to your treatment, so you can line up photos with events.
- Match photos to lab days if that makes it easier to remember. Our blood test timing planner helps you schedule draws.
- Note anything unusual, such as itching, redness, patches or clumps.
- Don’t count hairs in the shower. The AAD says losing 50 to 100 hairs a day is normal, so a few strands mean little.
This gives your prescriber or dermatologist a clear record instead of a vague worry.
Family history belongs in that record too. Ask relatives on both sides how their hairlines changed, and at what age. Because genes drive most male pattern hair loss, that history says more about your own path than your testosterone number does.
Write it down next to your photos, so it’s ready when a doctor asks. A dermatologist can then judge whether your pattern looks like your family’s, or like something else that needs a closer look.
What should you ask your prescriber?
Bring your photos and notes. Then ask:
- Does my hair loss look like the usual male pattern, or should I see a dermatologist?
- Could anything else, such as my thyroid or iron, be playing a part?
- If I want to try a hair-loss medicine, how would it affect my PSA results and my fertility?
- Is there anything about my treatment we should look at?
- Should I see a dermatologist now, while there’s more hair to keep?
Our guide to preparing for your TRT appointment has more questions to bring.