GHRP-2, GHRP-6, PEG-MGF & LL-37

All four peptides on this page are sold online as research chemicals and are not FDA-approved for any use. We group them separately from other Tier 3 entries because each carries a specific, named safety concern — not just an absence of human data. This page describes what's known — not dosing or usage guidance, and not a recommendation to use any of them. Talk to a doctor before considering any of them.

GHRP-2 and GHRP-6 are ghrelin-receptor-agonist growth hormone secretagogues, similar in mechanism concept to MK-677 but administered by injection. The FDA has specifically flagged GHRP-2 for reports of serious adverse events, including increased insulin requirements to maintain blood glucose, death among critically ill study subjects, infection, and pancreatitis — though causality in those reports has not been formally established. Both compounds are also associated with meaningful elevations in cortisol and prolactin, an effect that distinguishes them from more selective GH secretagogues. GHRP-6 is confirmed to remain on the FDA's Category 2 "significant safety risk" compounding list and was not part of the April 2026 removals. GHRP-2's status is less clean — some FDA compounding documentation places it in an "unevaluated" bucket under 503A rather than a confirmed Category 2 listing, alongside a separate, narrower 503B listing for injectable/nasal routes — but in either case it is not approved for compounding and not FDA-approved for any use.

PEG-MGF (pegylated mechano growth factor) is marketed around muscle repair and growth, based on the natural role of MGF/IGF-1Ec splice variants in muscle response to mechanical damage — but it has minimal clinical evidence behind it, and pegylation (a chemical modification used to extend half-life) introduces its own unstudied long-term safety questions in this context. LL-37 (Cathelicidin) is a naturally occurring antimicrobial peptide studied for wound-healing and immune effects, with limited human safety data specifically for the injectable, non-topical use it's marketed for.

Unlike GHRP-2 and GHRP-6, PEG-MGF and LL-37 were actually among the peptides the FDA removed from Category 2 effective April 22, 2026 — the same administrative action that affected BPC-157 and TB-500 — rather than compounds expected to stay restricted. That removal is not a safety clearance and doesn't mean approval is imminent: neither appeared on the FDA advisory committee's July 2026 docket for the compounding-permitted list, and FDA has indicated a separate future meeting will address the peptides not covered in July. In practice, their thin human-safety data keeps them in the same real-caution category as GHRP-2 and GHRP-6, even though their compounding paperwork status is technically different.

FDA — Bulk Drug Substances Used in Compounding →

None of these four peptides is FDA-approved for any use, and none is close to a compounding-permitted decision. GHRP-6 remains confirmed-restricted; GHRP-2 sits in an unresolved administrative category; PEG-MGF and LL-37 were removed from Category 2 in April 2026 but await a future advisory review before any compounding decision. All four are sold today only through unregulated online sellers, with no purity or dosing oversight, and each carries a specific, documented safety flag beyond the generic "not enough human data" caveat that applies across this tier.

FDA — Certain Bulk Drug Substances That May Present Significant Safety Risks (Category 2)