I honestly don't know. REAL human growth hormone is expensive, unstable, and MUST be administered under expert medical supervision. There is no other way to do it, unless you want to potentially mess yourself up beyond belief.
It is very questionable that multilevel marketing companies who hawk these "secretogogues" and "enhancers" have the scientific depth to engineer a substance that will effect the release of HGH from the pituitary gland in a controlled manner.
I once ordered such a product and tested it on myself. Yes, there were strong results, but ones more consistent with thyroid hormone. Sure, more energy, racing heart, high blood pressure, felt younger, kinda sorta, but too much thyroid hormone in a body that doesn't need it is a severe stressor.
There is a HGH marker test. If you feel like you want to know more, you can join the Life Extension Foundation (lef.org) and sign on for their blood tests they have contracted with LabCorp.
For any and all, I'd suggest the "male panel" for men, or the "female panel" for women, both are really thorough screenings of blood, liver, hormone, etc. functions, but they don't accept insurance payments, so it's going to be your dime.
LEF offers additional tests, a la carte, including DHT (too much of this will make you bald and look aged before your time, and swell your prostate to boot) and they offer the IGF-1 marker test for HGH.
If you intend to get involved with HGH replacement therapy, this marker should be known before you proceed, and low enough to justify HGH injections (can't get it any other way). Once a patient is receiving HGH injections, he or she will have to be carefully monitored, because HGH can have SERIOUS side effects...
You should also look to your DHEA-S levels (that's the bloodborne DHEA) relative to your age. If your DHEA levels are low, as mine were, DHEA (in my case keto-dhea) may be the more appropriate solution.
I have read the labels on some of the powdered "secretogogue" products, and found them to contain high levels of arginine. Arginine may have the unwanted side effect of activating or worsening herpes class viral infections, therefore I would avoid loading myself with arginine.
here's a link to lef.org that you may find useful