GHRP-6 is a potent stimulator of natural Growth Hormone release. GHRP-6 is a Hexa-peptide that promotes food intake by stimulating hunger and helps increase energy metabolism. Growth Hormone Releasing Peptides, similar to GHRP-6, are most commonly used for treatment of Growth Hormone (GH) deficiencies, eating disorders, obesity, etc. Research has shown that use of these HGH Peptides increases lean muscle mass, strength, stamina and decreases body fat.
 
GHRP-2 vs GHRP-6
The main difference is growth hormone releasing peptide-6 gives a considerable increase in appetite being synthetic ghrelin; it is exceptionally potent in this regard.
Ghrelin is a peptide that is released naturally in the lining of the stomach that increases gastric emptying and hunger. IGF-1 boosts the body's ability to build muscle and burn fat.  
GHRP-2 & 6 both increase levels of circulating growth hormone and may cause the liver to secrete the hormone IGF-1.Food intake is where GHRP-6 is going to outshine other GHRP peptides. This is mainly due to the fact that GHRP-6 is known to drastically increase hunger, which normally occurs within an hour after injection. The extreme hunger has been linked to the increase of ghrelin within the stomach. Ghrelin is a hormone that is produced by cells in the stomach that are released due to the stomach being empty or if the stomach thinks it is empty. Ghrelin not only aids in stimulating GH release, but it also helps regulate appetite, promote fat loss in muscle tissues and helps in healing damaged tendons. Studies suggest that elevated levels of ghrelin in the stomach have been shown to have a direct link with fast healing of damaged tissues. This is why GHRP-6 may be a better option for healing than the newer modified version GHRP-2. GHRP-2 works the same as GHRP-6 but the extreme hunger side effect is not as severe.