Feb 21 2015
Hexarelin, a potent growth hormone (GH)-releasing peptide,
is capable of causing profound HGH
release in normal individuals.
Ghrelin and its synthetic analog hexarelin are specific ligands of growth hormone secretagogue (GHS) receptor. GHS have strong growth hormone-releasing effect and other neuroendocrine activities such as stimulatory effects on prolactin and adrenocorticotropic hormone secretion.
Anal Chem. 2012. Metabolism of growth hormone releasing peptides. New, potentially performance enhancing compounds have frequently been introduced to licit and illicit markets and rapidly distributed via worldwide operating Internet platforms. Developing fast analytical strategies to follow these new trends is one the most challenging issues for modern doping control analysis. Even if reference compounds for the active drugs are readily obtained, their unknown metabolism complicates effective testing strategies. Recently, a new class of small C-terminally amidated peptides comprising four to seven amino acid residues received considerable attention of sports drug testing authorities due to their ability to stimulate growth hormone release from the pituitary. The most promising candidates are the growth hormone releasing peptide (GHRP)-1, -2, -4, -5, -6, hexarelin, alexamorelin, and ipamorelin. With the exemption of GHRP-2, the entity of these peptides represents nonapproved pharmaceuticals; however, via Internet providers, all compounds are readily available.
Safety, adverse reactions, side effects
Not enough human studies are available to know the safety profile of this substance. It is a good idea to take frequent breaks from use.
Psychoneuroendocrinology. 2004. Hexarelin decreases
slow-wave sleep and stimulates the secretion of GH, ACTH, cortisol and prolactin
during sleep in healthy volunteers.
Ghrelin, the endogenous ligand of the growth hormone (GH) secretagogue (GHS) receptor and some GHSs exert different effects on sleep electroencephalogram (EEG) and sleep-related hormone secretion in humans. Similar to GH-releasing hormone (GHRH) ghrelin promotes slow-wave sleep in humans, whereas GH-releasing peptide-6 (GHRP-6) enhances stage 2 nonrapid-eye movement sleep (NREMS). As GHRP-6, hexarelin is a synthetic GHS. Hexarelin is superior to GHRH and GHRP-6 in stimulating GH release. The influence of hexarelin on sleep-endocrine activity and the immune system is unknown. We investigated simultaneously the sleep EEG and nocturnal profiles of GH, ACTH, cortisol, prolactin, leptin, tumor necrosis factor (TNF)-alpha, and soluble TNF-alpha receptors in seven young normal volunteers after repetitive administration of 4 x 50 microg hexarelin or placebo at 22.00, 23.00, 24.00 and 01.00 h. Following hexarelin, stage 4 sleep during the first half of the night, and EEG delta power during the total night decreased significantly. Significant increases of the concentrations of GH and prolactin during the total night, and of ACTH and of cortisol during the first half of the night were found. Leptin levels, TNF-alpha and soluble TNF receptors remained unchanged. We hypothesize that sleep is impaired after hexarelin since the GHRH/corticotropin-releasing hormone (CRH) ratio is changed in favour of CRH. There are no hints for an interaction of hexarelin and the immune system.
Growth Horm IGF Res. 1998. Does desensitization to hexarelin occur?
Department of Endocrinology, Christie Hospital NHS Trust, Manchester, UK. Hexarelin, a potent growth hormone (GH)-releasing peptide, is capable of causing profound GH release in normal individuals. If the GH response to hexarelin in humans becomes appreciably attenuated following long-term administration, this would seriously limit the potential therapeutic use of hexarelin and similar agents. The effect of twice-daily subcutaneous injections of hexarelin on GH release was therefore investigated over a period of 16 weeks in 12 healthy elderly individuals. There was a significant change in AUCGH over the study period (P = 0.0003). Further analysis showed that the decreases in AUCGH at weeks 4 and 16 were significant compared with baseline values. Four weeks after completion of the 16-week study period, hexarelin was again administered. On this occasion, AUCGH increased significantly compared with that at week 16 and was not significantly different compared with that at week 0. These results show that attenuation of the GH response after long-term hexarelin therapy is partial and reversible.