We all know AAS have a negative impact on the bodies own production of T. HPTA axis, feedback, all that. Iow, that the body sees exogenous T (or close cousins of T) and ramps down its own production of same.

We also hear that IGF has no impact on the HPTA (I hate when people say HPTA Axis. It's kind of like saying VIN Number).

My question is - any possibility that IGF (I'm talking the Long R3 stuff) has a negative impact on the body's own production of GH/Igf/etc (while exogenous IGF is present, of course)? I am not sure if there is a term for this loop, like there is with HPTA and AAS.

My understanding is that the long version of IGF stops working after a month or so, but I have heard this is because the body basically "recognizes" it or some such, not due to feedback loop issues.

Whether or not there is a feedback loop would have a # of implications. For example, probably would be better not to inject immediately before bedtime *if* this was the case, as the body produces lots of GH in certain stages of sleep and you wouldn't want to inhibit that with a large pulse right before bedtime. Otoh, if this is not an issue (feedback loop), then it's not an issue.

Lots of other implications as well.