What is Ipamorelin?
Ipamorelin: Pentapeptide ghrelin-receptor (GHS-R) agonist, described as the first 'selective' GH secretagogue because it releases GH without raising ACTH/cortisol. The sources cited here most often discuss it for: Selective GH release, animal; Gut motility, negative trial; Sleep and body composition, anecdotal. Evidence label: Preclinical.
- Type
- Peptide
- Family
- Growth Hormone Axis
- Evidence label
- Preclinical (2 of 5)
- Regulatory status
- Ipamorelin acetate has been in FDA's 503B compounding Category 2 (significant safety risks) since September 29, 2023, and FDA also lists a withdrawn ipamorelin acetate nomination that was previously in Category 2.
- Goals discussed
- Hormones & Fertility, Gut & Digestion, Sleep, Muscle & Tone, Fat Loss & Metabolism
- Also called
- NNC 26-0161, Aib-His-D-2-Nal-D-Phe-Lys-NH2, Ipamorelin acetate, ipam, Ipam
- Last reviewed
- 2026-10-11
- Pentapeptide ghrelin-receptor (GHS-R) agonist, described as the first 'selective' GH secretagogue because it releases GH without raising ACTH/cortisol; not FDA-approved; FDA placed ipamorelin in compounding Category 2 (2023) citing immunogenicity and serious adverse events incl. death with IV use.12
Regulatory status Ipamorelin acetate has been in FDA's 503B compounding Category 2 (significant safety risks) since September 29, 2023, and FDA also lists a withdrawn ipamorelin acetate nomination that was previously in Category 2. 2
Names as used in gyms, forums and gray-market listings. Reported, not endorsed; stacks have not been studied as combinations.
Very surprisingly, ipamorelin did not release ACTH or cortisol in levels significantly different from those observed following GHRH stimulation.
Abstract of the original Novo Nordisk pharmacology paper; findings are from rat pituitary cells, rats and swine, not humans.
What is Ipamorelin researched for?
The three outcomes most discussed for Ipamorelin in the sources below, as those sources report them. humanpeptides.fyi makes no claims of its own: a listed benefit can be unproven or can have failed in trials, and the label on each line says which.
What do researchers and users say about Ipamorelin?
There were no significant differences between ipamorelin and placebo in the key and secondary efficacy analyses.
Conclusion of a phase 2, double-blind, placebo-controlled trial in 114 adults after bowel surgery; the drug was well tolerated but did not speed recovery of gut function.
A study published in literature identified serious adverse events including death when ipamorelin was administered intravenously for improving gastric motility.
FDA compounding safety listing; FDA does not name the study. The published IV gut-motility trial (Beck et al., 2014) reported adverse events in 87.5% on ipamorelin vs 94.8% on placebo.
What side effects of Ipamorelin are reported?
- FDA: immunogenicity risk from aggregation/impurities; serious adverse events incl. death reported with IV use; insufficient data for subcutaneous use2
- Users report water retention/facial puffiness, increased hunger, sleep disruption if mistimedanecdotal89
- Tingling in the hands and feet is listed as a possible side effect alongside water retention and hunger.clinical reference site10
- Growth-hormone-releasing peptides carry a theoretical concern about fueling tumor growth in people with active cancer.theoretical11
What do peptide guides say about Ipamorelin?
- Dr. Axe Dr. Axe's peptide library notes that FDA reviewed ipamorelin for growth-hormone-related uses and found insufficient effectiveness data, and it grades the CJC-1295/ipamorelin entry as insufficient evidence. 12
- Dr. Axe Dr. Axe's guide points out that the World Anti-Doping Agency list includes growth hormone releasing peptides such as ipamorelin, so it is off-limits for athletes in tested sport. 13
- PepEdHub PepEdHub describes ipamorelin as a highly selective ghrelin-receptor agonist that releases growth hormone in natural-looking pulses without meaningfully raising cortisol, prolactin or ACTH, and calls its side-effect profile the mildest in its class. 10
- Seek Peptides Seek Peptides lists ipamorelin as a selective growth hormone releaser promoted for body recomposition, recovery and sleep, usually paired with CJC-1295; these are use claims, not trial results. 11
- NCBI PMC In a rat model of postoperative ileus, intravenous ipamorelin sped stomach emptying by restoring gastric muscle contractions, an animal result the later human phase 2 trial did not confirm. 14
What does the research say, system by system?
Body & tissues1
- GI tract (prokinetic ghrelin-mimetic, tested for ileus)4
Hormones & physiology2
Brain, mood & sleep1
- Anecdotal improved sleep depth; timing affects sleep for some users6
Weight & metabolism1
- No controlled data; anecdotal recomposition reports15
Muscle1
- No human outcome data found; theorized via GH/IGF-11
Also notable1
- FDA proposed (Oct 2024 PCAC) not adding ipamorelin to the 503A bulks list16
How strong is the evidence for Ipamorelin?
Animal pharmacology + one negative human phase 2 (ileus); body-composition/sleep claims anecdotal
Mostly cell and animal studies. Human effects unknown. How tiers work
Questions about Ipamorelin
What is Ipamorelin?
Pentapeptide ghrelin-receptor (GHS-R) agonist, described as the first 'selective' GH secretagogue because it releases GH without raising ACTH/cortisol.
Is Ipamorelin FDA-approved?
Ipamorelin acetate has been in FDA's 503B compounding Category 2 (significant safety risks) since September 29, 2023, and FDA also lists a withdrawn ipamorelin acetate nomination that was previously in Category 2.
What is Ipamorelin researched for?
The sources cited on this page most often discuss three outcomes: Selective GH release, animal; Gut motility, negative trial; Sleep and body composition, anecdotal. Each line above shows what the source reports and how strong that evidence is.
What side effects of Ipamorelin are reported?
Reported in the cited sources: FDA: immunogenicity risk from aggregation/impurities; serious adverse events incl. death reported with IV use; insufficient data for subcutaneous use; Users report water retention/facial puffiness, increased hunger, sleep disruption if mistimed; Tingling in the hands and feet is listed as a possible side effect alongside water retention and hunger. The list is not complete, and few listed risks does not mean a compound is safe.
How strong is the evidence for Ipamorelin?
Evidence label: Preclinical. Animal pharmacology + one negative human phase 2 (ileus); body-composition/sleep claims anecdotal.
What else is Ipamorelin called?
Names used for it include NNC 26-0161, Aib-His-D-2-Nal-D-Phe-Lys-NH2, Ipamorelin acetate, ipam, Ipam.
Does humanpeptides.fyi recommend Ipamorelin?
No. humanpeptides.fyi makes no claims and no recommendations of its own. It summarizes and links to what others have published and posted. Nothing here is medical advice; talk to a licensed clinician.