I was referred to an endocrinologist who managed mine. I didn’t respond to the rub-on testosterone products, now get a shot weekly. My body flat stopped making T.
“My body flat stopped making T.”
Did that condition - “flat stopped” - precede or come after you started taking T treatments.
There are two parts of the body making T. Only one part is the body’s process that makes T. The other part is the body’s mechanism that monitor how much T is in circulation, and signal that more, or less ought to be made.
The first part can break down with age, and no matter the signals to make more, only make so much. But the second part CAN be short-circuited by supplementing what the body is making with T added into the body/bloodstream from outside the body. Then the mechanism to control the natural production of T starts getting a different reading; one that says the natural T production does not have to work as hard, and the body’s own T making could slow down even more.
That is why the best advice is towards the introduction of supplemental T to only, at the very most, bring T levels NEAR to the normal “average” for the person’s age and not to exceed it.
What I have not seen as clear is if any testing can differentiate T in the blood by source - the body or supplemental. That is what is needed to determine if excess supplemental T is actually causing the natural production to slow down from what it was before supplemental T was introduced.
Personally, after testing, I would try all the things folks say can be done to get the natural T production raised without any supplemental T, before trying any supplemental T.