The differences are in which compounds each one carries, the format (oral vs injection vs nasal), and how pricing is structured
GHK-Cu is a reasonable addition after these basics, not a substitute for them
Research also points to its potential to regulate the neuroendocrine system, normalise melatonin production, and support immune function
As for individuals misusing GH for recreational and athletic performance-enhancing purposes, GH, IGF-I and insulin levels are increased suggesting that insulin sensitivity is worsened and iatrogenic acromegaly is induced, especially if used long-term
at Kyungpook National University published a randomized, double-blind, placebo-controlled trial in Annals of Dermatology (2016) testing GHK combined with 5-aminolevulinic acid (5-ALA) on 45 men with male pattern hair loss over six months