Quick Comparison
| BPC-157 | Hexarelin | |
|---|---|---|
| Half-Life | 4 hours (stable in gastric juice) | 1.2 hours |
| Typical Dosage | Standard: 200-800 mcg subcutaneous once daily, or 500-1000 mcg oral once daily. Often cycled 4-6 weeks on, 2 weeks off. Injectable may be administered near the injury site for localized healing. Oral route used primarily for gut-related conditions. | Standard: 100-200 mcg subcutaneous two or three times daily on an empty stomach. Must be cycled — desensitization occurs within 2-4 weeks of continuous use. Typical cycling: 2 weeks on, 2 weeks off. |
| Administration | Subcutaneous injection, intramuscular injection, or oral | Subcutaneous injection |
| Research Papers | 30 papers | 6 papers |
| Categories |
Mechanism of Action
BPC-157
BPC-157 is a synthetic pentadecapeptide (15 amino acids) derived from a protective protein found in human gastric juice. Its mechanism of action is remarkably multifaceted, affecting multiple organ systems and healing pathways simultaneously, which is unusual for a single peptide. The primary mechanism centers on the nitric oxide (NO) system — BPC-157 modulates both constitutive (eNOS) and inducible (iNOS) nitric oxide synthase, and can either promote or inhibit NO production depending on the tissue context and injury state.
BPC-157's regenerative effects are mediated through upregulation of multiple growth factors. It increases expression of vascular endothelial growth factor (VEGF), promoting angiogenesis — the formation of new blood vessels at injury sites, which is critical for delivering oxygen and nutrients for tissue repair. It also upregulates epidermal growth factor (EGF), nerve growth factor (NGF), and hepatocyte growth factor (HGF) receptors, supporting wound healing, nerve regeneration, and organ protection respectively. In tendon and ligament injuries, BPC-157 stimulates fibroblast migration and proliferation, accelerating collagen deposition and organized tissue repair rather than scar formation.
Beyond structural healing, BPC-157 has significant effects on the central and enteric nervous systems. It modulates dopaminergic, serotonergic, GABAergic, and opioid systems, which may explain reported effects on mood, gut function, and pain perception. It protects endothelial function, counteracts the effects of NSAIDs on the gastric mucosa, and has demonstrated cytoprotective effects in models of liver, brain, heart, and intestinal damage. The peptide also interacts with the FAK-paxillin pathway, which is central to cell adhesion and migration during wound healing. Its stability in gastric juice — unusual for a peptide — enables oral administration, making it one of the few peptides effective by both injectable and oral routes.
Hexarelin
Hexarelin is a synthetic hexapeptide (His-D-2-MeTrp-Ala-Trp-D-Phe-Lys-NH2) that acts as one of the most potent agonists of the growth hormone secretagogue receptor (GHS-R1a). Its strong receptor affinity produces the highest GH release amplitude among the GHRP family, but this potency comes with broader neuroendocrine activation compared to more selective agents like ipamorelin.
At the pituitary level, hexarelin binding to GHS-R1a activates Gq/11-coupled phospholipase C, generating IP3 and DAG. IP3-mediated calcium release from intracellular stores triggers massive GH vesicle exocytosis. The strong GH response also comes with significant stimulation of cortisol (via ACTH release from corticotrophs) and prolactin release from lactotrophs — side effects that limit its clinical utility compared to more selective secretagogues.
Uniquely among GHRPs, hexarelin demonstrates significant cardioprotective properties independent of GH release. GHS-R1a receptors are expressed on cardiomyocytes, and hexarelin binding activates survival signaling through the PI3K/Akt and ERK1/2 pathways, protecting cardiac cells from ischemia-reperfusion injury and apoptosis. Hexarelin also binds to the scavenger receptor CD36 on macrophages and cardiac tissue, which may contribute to its anti-atherosclerotic and cardioprotective effects. Animal studies have demonstrated reduced infarct size and improved cardiac function following hexarelin administration. However, a significant practical limitation is desensitization — continuous hexarelin use leads to progressive reduction in GH response within 2-4 weeks, necessitating cycling protocols to maintain effectiveness.
Risks & Safety
BPC-157
Common
nausea, dizziness, mild headache, injection site irritation.
Serious
no completed human studies, so long-term effects are unestablished.
Rare
allergic reactions, theoretical concern about promoting new blood vessel growth in existing tumors.
Hexarelin
Common
elevated cortisol, elevated prolactin, water retention, increased appetite, headache.
Serious
desensitisation after 2-4 weeks of continuous use, breast tissue growth in men from prolactin elevation.
Rare
severe water retention, wrist pain/numbness.
Full Profiles
BPC-157 →
A healing compound made from a protein found in stomach fluid. It's the most studied peptide for tissue repair, with research showing it helps heal tendons, ligaments, muscles, the gut, and other organs. It's stable enough to survive stomach acid, so you can take it either by injection under the skin or by mouth.
Hexarelin →
The most powerful growth hormone releasing peptide available — it triggers the biggest GH spike of any GHRP. Also uniquely protective for the heart, which has made it interesting for cardiac research. The downside is that its potency comes with more side effects than gentler options like Ipamorelin: it raises cortisol (stress hormone) and prolactin more than any other GHRP, and your body builds tolerance within 2-4 weeks, requiring cycling.