N° 014 · The Directory

Ipamorelin

Selective GHRP. The other half of the CJC-1295 stack, with a cleaner side-effect profile than older GHRPs.

A-Tier Body Comp & GH Rx via compounding

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What it does - plain English

Ipamorelin is a selective GHRP (growth hormone-releasing peptide) that stimulates your pituitary gland to release growth hormone. It works through a different receptor than CJC-1295 - Ipamorelin works on the ghrelin receptor, CJC-1295 on the GHRH receptor - which is why the two are so commonly stacked together: hitting both receptors produces a larger GH pulse than either alone.

Compared to older GHRPs like GHRP-2 and GHRP-6, Ipamorelin is more selective. It raises GH without significantly raising cortisol (the stress hormone), prolactin (a hormone linked to appetite and other effects), or appetite itself. That selectivity is why most modern peptide protocols default to Ipamorelin instead of GHRP-2 or GHRP-6.

It is not a steroid. It is not synthetic growth hormone. It tells your pituitary gland to release more of the growth hormone your body already makes - nothing more.

Status

A-tier within body-composition and GH-supplementation protocols. Pharmacokinetic studies confirm acute GH release without the cortisol and appetite side effects of older GHRPs. The CJC-1295/Ipamorelin combination is the most-prescribed peptide stack in functional medicine and anti-aging telehealth practices.

Long-term safety data in healthy adults is thinner than for FDA-approved drugs. The evidence base here is: strong animal pharmacology, solid short-term human PK data, one Phase 2 clinical trial in surgical patients, and a large volume of clinical experience from compounding physicians - not a typical FDA approval package.

Legal status

Ipamorelin is not FDA-approved for any use in humans. The pharmaceutical version (NN703) was investigated for postoperative ileus - a temporary intestinal slowdown that can follow surgery - but development was halted at Phase 2 in 2007 and was never submitted for approval.

What this means in practice: you cannot buy Ipamorelin over the counter. The common routes are:

Compounding pharmacy via telehealth prescription - the legal route. A licensed provider writes the script; a compounding pharmacy ships sterile vials. Often co-prescribed with CJC-1295 in a single combination injection. Availability varies by state.
Research peptide vendors - sold as "for research purposes only, not for human consumption." The peptide may be high-quality, but you have no consumer protection and no regulatory oversight of the supplier.
Don't - your primary care physician or sports-medicine doc may advise against it pending longer-term human data. That is a defensible position.

Where to source

Always ask for a COA (Certificate of Analysis - the lab report proving the bottle contains what the label says, at the purity stated). No COA, no buy. Period.

The combination compounded prescription - Ipamorelin plus CJC-1295 in one vial - is the cleanest sourcing path. One prescription, one injection, one COA per batch from a licensed pharmacy.

Compounding pharmacy via telehealth - legal route, prescription required, COA per batch, often combined with CJC-1295 in one bottle. The default recommendation for anyone pursuing this seriously.
Research peptide vendors - sold for research use only. Specific vendor reviews and price snapshots are in the weekly dispatch when relevant.

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Two studies worth reading

Selective GH release without cortisol bump

Raun, K. et al., European Journal of Endocrinology

The 1998 paper that introduced Ipamorelin and demonstrated its selectivity advantage over earlier GHRPs. Shows robust GH release with no significant effect on cortisol, prolactin, or ACTH across dose ranges. Foundational read for understanding why modern peptide protocols default to Ipamorelin over older secretagogues.

Postoperative ileus trial - where pharmaceutical development stopped

Beck, D. et al., Journal of Gastrointestinal Surgery

Phase 2 trial showing safety and tolerability in 130 postoperative patients. The closest thing to a controlled human safety dataset for the peptide. Development was halted not for safety reasons but for efficacy thresholds in the specific surgical indication - the safety profile held up.

From the Editor

My take: Ipamorelin is the GHRP that actually deserves the "clean" reputation it has. The selectivity for GH - without cortisol or appetite spikes - is real and well-documented, not marketing copy. If you are researching GH-stimulating protocols, Ipamorelin is the right secretagogue half of the stack.

What I'd tell my dad: Ipamorelin alone has minimal effect. It works synergistically with a GHRH analog like CJC-1295 or Sermorelin - a GHRH analog tells your pituitary "it's time to release GH," Ipamorelin amplifies that pulse via a second receptor. The whole protocol matters; solo Ipamorelin is mostly not worth doing. If a clinician proposes Ipamorelin alone for body composition, ask why they are not stacking it with a GHRH analog.

What I'd skip: "growth hormone cocktails" that mix Ipamorelin with multiple older GHRPs - GHRP-2, GHRP-6, MK-677 - in one formulation. The entire advantage of Ipamorelin is selectivity. Layering on older GHRPs erases that advantage and brings back the cortisol and appetite side effects you were trying to avoid. One GHRP plus one GHRH analog. That's the stack.

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Last reviewed · 2026·05·04 · Status reviewed weekly