Description
Of the early growth hormone secretagogues that came out of the 1990s discovery push, Ipamorelin is the one that researchers still reach for when they want a clean signal. Its development code, NNC 26-0161, traces back to a Novo Nordisk programme looking for short GHRP analogues that triggered GH release without dragging cortisol and prolactin up with them. The team landed on a five-residue sequence, and that pentapeptide is what sits in the vial we ship.
Where it fits among the GHRPs
Most of the named growth hormone-releasing peptides, including GHRP-2 and GHRP-6, are hexapeptides. Ipamorelin is shorter by one residue, and that shorter chain produced an unusually selective profile in the original animal work. GH release through GHSR-1a was preserved. Activation of the ACTH and prolactin axes that complicates other GHRP studies was not detectable at active doses. For an in vitro project that needs a single-axis readout, that selectivity is the reason the molecule keeps showing up in protocols 25 years after it was first described.
What is actually in the vial
- Mass: 5mg lyophilised peptide, white powder, sealed under inert gas
- Sequence: Aib-His-D-2-Nal-D-Phe-Lys-NH2 (the original NNC 26-0161 pentapeptide)
- Purity: >98% by reversed-phase HPLC, confirmed by mass spectrometry on the same lot you receive
- Form: acetate salt, single-use rubber-stopper glass vial
- Origin: synthesised inside the UK and EU, not relabelled bulk from unverified offshore suppliers
How researchers tend to use it
The half-life in animal models is roughly two hours, which makes Ipamorelin a useful tool for pulse-dose work where a brief, time-locked GH signal is wanted rather than a continuous one. In published research it shows up on its own in selectivity studies, and paired with CJC-1295 in protocols designed to separate the GHRH arm of the axis from the ghrelin-receptor arm. Whichever side of that comparison your assay is on, batch consistency between vials is the thing that decides whether your data is reproducible.
Sourcing, paperwork, and how we run the orders
Every batch is HPLC-traced and MS-confirmed before the lot leaves the bench, and the CoA travels in the box with the product. If a vial doesn’t match its paperwork, you get a refund. Not a store credit, an actual refund. Around 90% of UK orders arrive inside 48 hours because we ship from a UK warehouse with no customs handoff. The live chat during UK office hours is staffed by people, not a bot, and if you need ten vials or more for a longer-running study, the team will quote bulk pricing per lot through that same channel.
Sold strictly for in vitro laboratory research. Not for human or veterinary use. UK 18+.

