No, growth hormone (GH) cannot cause permanent hair loss.
However, it can cause temporary shedding.
Let's clarify the difference between androgenic alopecia and temporary shedding.
Androgenic alopecia, or male pattern baldness, is the acceleration of hair follicle miniaturization facilitated via androgen receptor activation, which is what most guys experience throughout their lives.
Shedding is often misinterpreted as permanent loss.
Temporary shedding is caused when a large percentage of scalp hairs are shifted into the shedding phase of the hair growth cycle.
This life cycle is fairly long as your hair goes through a growth phase and eventually completes the life cycle and falls out of your head.
However, certain deficiencies, autoimmune triggers, allergens, or hormone fluctuations can cause a premature shift of hairs in the anagen phase to the telogen phase.
GH Hair Loss And Shedding
Human growth hormone, as you may know, has a lot of anti-aging benefits when it comes to complexion, hair, skin, nails, etc. (to a point, this benefit is often massively exaggerated).
Then why have some people reported hair loss from it?
Here's basically the lowdown on it.
Human growth hormone will more than likely improve the quality of your hair if you don't have top tier endogenous secretion.
It's going to improve how fast it grows and perhaps even prolong the anagen phase, which indirectly is going to increase overall visual density.
My personal hair loss prevention regimen has often included MK-677 which is a GH secretagogue, or low dosages of synthetic GH injections.
I've utilized both to stimulate a healthier rate of growth, which indirectly offsets some loss of density I had in my own hair, and it makes a noticeable difference.
The mechanism of action behind GH causing hair loss in some individuals boils down to the simple fact that hormonal fluctuations can trigger telogen effluvium.
When you introduce something hormonal into your system that causes a temporary imbalance (your body has to adjust to and acclimate and get back to a state of hormonal homeostasis), it can cause shedding.
Non-Androgenic Triggers That Can Cause Shedding
There are plenty of triggers that are completely non-androgenic that can cause shedding.
There are some people with autoimmune disorders and allergies that cause hair to just fall out of their head.
Chemotherapy can also cause all of your hair to fall from your head.
Essentially, if you use something that your body just doesn't agree with, it can cause a shed.
For example, a change in your hormonal profile or a chemical that alters your microbiome significantly.
There's a number of things that can cause shedding.
Take hypothyroidism as a perfect example.
Hypothyroidism causes your hair to fall out.
Is that permanent? No, it's not.
If you're using too much exogenous T3 to treat your hypothyroidism you can cause massive amounts of shedding too.
There are tons of things that cause shedding that have nothing to do with androgenic alopecia/male pattern baldness.
GH Does Not Miniaturize Hair Follicles
Hair follicles are not inhibited by GH and IGF-1 like they are with androgens.
As there is no miniaturization occurring, permanent loss via GH administration would be impossible.
Especially when considering the fact that the GH/IGF-1 pathway is partially what is responsible for optimal hair growth to begin with.
When you first start taking GH, you may experience a big shed.
This shed should be short-lived though, pending one was consistently using the same dosage with a fixed administration frequency.
Achieving stable hormone concentrations is one of the main keys in preventing unnecessary shedding phases.