For the list of amino acids that follows, studies have shown some of them to exhibit their own particular beneficial effects, in addition to their effects as HGH releasers.

Arginine - No doubt the amino acid most commonly used as a secretogogue is arginine. The study by Doctor Isadori and colleagues in Rome showed that as an HGH releaser, Arginine with Lysine even outperformed L-dopa. Arginine has also been shown to increase the body's production of NO (nitric oxide), which allows for penile erections. In addition, its performance as a secretogogue can be enhanced still further when taken in conjunction with other specific amino acid salts.

Lysine - Besides acting on its own in the body by stimulating the secretion of thymic hormone, and by augmenting the body in its use of IGF-1, lysine also provides a synergistic effect when used in conjunction with arginine. Taken together, lysine and arginine make up one of the most commonly used combinations in secretogogue preparations.

Ornithine - Frequently paired with arginine as well, is the amino acid, ornithine. Given that arginine is a biochemical precursor to ornithine, it is not surprising that besides having a synergistic effect with arginine, on its own it also provides some of the same benefits conferred by arginine. In a study by Dirk Pearson and Sandy Shaw, it was found that taking 5 to 10 grams of this non-essential amino acid on an empty stomach at bedtime appeared to cause HGH secretion to double, although the effects of long term ingestion of such a large amount of this one amino acid are unknown. Ornithine has also been shown to bolster the immune system, aid in liver regeneration, and effect ammonia detoxification. Ornithine is also found in high concentrations in the skin and connective tissue, suggesting that it may well be useful in maintaining and repairing these tissues. As well, ornithine serves as a precursor of the amino acids citrulline, proline, and glutamic acid.

Glutamine - Instrumental on its own in raising the levels of HGH, Glutamine is also an integral component of the brain's biochemistry, particularly as to its being converted to glutamic acid. It has also been shown to have a strong effect on the expansion and firmness of muscle.