Peptide Protocol IQ
Unapproved research chemicalNo human evidenceProhibited in sport

Ipamorelin

Also referred to as NNC 26-0161

A GH secretagogue reported as more selective than earlier compounds in the class. The evidence is pharmacodynamic, not outcome-based.

Molecule class
Selective growth hormone secretagogue (ghrelin receptor agonist)
Category
GH axis
Last evidence review
2026-08-23
2
Human studies
1
Animal / in vitro
1
Graded claims
114
Participants

Derived from qualifying human evidence

  • Most commonly studied duration: 1 weeks. Most frequently reported duration among 1 qualifying human study with a stated duration.
  • Longest qualifying human study: 1 weeks. Longest duration among qualifying human studies with a stated duration.

These figures are computed from the study records shown below. Records without a verified source identifier are excluded from the calculation.

Mechanism

What is being studied

Agonises the GHS-R1a (ghrelin) receptor to stimulate growth hormone release, reported with less effect on cortisol and prolactin than earlier secretagogues.

Evidence

Claims, graded individually

Each statement below carries its own evidence level, its own confidence rating, and its own account of what remains unestablished. A compound does not have a single grade.

GH-Axis Research

EMechanisticLow confidenceNo human evidence

Ipamorelin has been reported to stimulate growth hormone release with greater selectivity than earlier secretagogues in the models studied.

What is not established

A hormone-release signal is a pharmacodynamic observation, not a clinical outcome. No long-term human outcome or safety data exist.

Supporting sources (3)
Randomised controlled trialHuman Identifier verified

Ipamorelin for the treatment of postoperative ileus after bowel resection: a randomised, placebo-controlled phase 2 trial

Beck DE, Sweeney WB, McCarter MD, et al. · International Journal of Colorectal Disease · 2014 · n = 114

Population
Adults undergoing partial bowel resection
Endpoint
Time to first tolerated solid food
Route
Intravenous
Quantity as reported
0.03 mg/kg per administration, twice daily
Frequency
Twice daily from postoperative day 1 until discharge or day 7
Duration
1 weeks

Result. 25.3 hours versus 32.6 hours for placebo. The difference was not statistically significant (p=0.15).

Adverse events. No significant safety signal over the short treatment period.

Limitations. This is the only human randomised trial of ipamorelin at any dose, it is a negative result, and the amount used, about 2 mg per administration intravenously for a 70 kg adult, is roughly ten times what is sold for subcutaneous use.

Pharmacokinetic studyAnimalNo verified identifier on file

Ipamorelin as a selective growth hormone secretagogue: pharmacology literature

Multiple · Various endocrinology and pharmacology journals · 2018

Population
Animal pharmacology; limited early human pharmacodynamic work
Endpoint
Growth hormone release and selectivity versus cortisol and prolactin
Route
Intravenous and subcutaneous
Quantity as reported
Reported in early pharmacology work; no established human protocol
Frequency
Varies

Result. Reported to release growth hormone with greater selectivity than earlier secretagogues in the models studied.

Adverse events. Not established in sustained human use.

Limitations. A pharmacodynamic signal is not a clinical outcome. No adequate long-term human outcome or safety data.

Systematic reviewHuman Identifier verified

Peptide therapeutics in musculoskeletal medicine: a review of the evidence

Multiple · American Journal of Sports Medicine · 2026

Population
Review of the published literature on peptides marketed for musculoskeletal use
Endpoint
State of the evidence for musculoskeletal indications

Result. Concludes that no clinical data support the use of GHK-Cu for musculoskeletal conditions, that CJC-1295 and ipamorelin synergy data is murine only, that tesamorelin has no supporting orthopaedic evidence, and that for the class generally the indications, amounts, frequency and duration of treatment remain unknown.

Adverse events. Not an outcome of the review.

Limitations. A narrative review, not a meta-analysis. It is catalogued because it is the most recent peer-reviewed statement of how thin this evidence base is, and because it is the counterweight to every vendor page that implies otherwise.

Last evidence review: 2026-08-23

Human evidence

2 human studies catalogued

Human and non-human evidence are kept strictly separate. They are never pooled, averaged, or presented as a single body of support.

Randomised controlled trialHuman Identifier verified

Ipamorelin for the treatment of postoperative ileus after bowel resection: a randomised, placebo-controlled phase 2 trial

Beck DE, Sweeney WB, McCarter MD, et al. · International Journal of Colorectal Disease · 2014 · n = 114

Population
Adults undergoing partial bowel resection
Endpoint
Time to first tolerated solid food
Route
Intravenous
Quantity as reported
0.03 mg/kg per administration, twice daily
Frequency
Twice daily from postoperative day 1 until discharge or day 7
Duration
1 weeks

Result. 25.3 hours versus 32.6 hours for placebo. The difference was not statistically significant (p=0.15).

Adverse events. No significant safety signal over the short treatment period.

Limitations. This is the only human randomised trial of ipamorelin at any dose, it is a negative result, and the amount used, about 2 mg per administration intravenously for a 70 kg adult, is roughly ten times what is sold for subcutaneous use.

Systematic reviewHuman Identifier verified

Peptide therapeutics in musculoskeletal medicine: a review of the evidence

Multiple · American Journal of Sports Medicine · 2026

Population
Review of the published literature on peptides marketed for musculoskeletal use
Endpoint
State of the evidence for musculoskeletal indications

Result. Concludes that no clinical data support the use of GHK-Cu for musculoskeletal conditions, that CJC-1295 and ipamorelin synergy data is murine only, that tesamorelin has no supporting orthopaedic evidence, and that for the class generally the indications, amounts, frequency and duration of treatment remain unknown.

Adverse events. Not an outcome of the review.

Limitations. A narrative review, not a meta-analysis. It is catalogued because it is the most recent peer-reviewed statement of how thin this evidence base is, and because it is the counterweight to every vendor page that implies otherwise.

Preclinical evidence

Animal and in-vitro research

Kept separate deliberately. Most preclinical findings do not translate to humans, and animal quantities expressed per kilogram do not convert to human quantities by simple arithmetic.

Pharmacokinetic studyAnimalNo verified identifier on file

Ipamorelin as a selective growth hormone secretagogue: pharmacology literature

Multiple · Various endocrinology and pharmacology journals · 2018

Population
Animal pharmacology; limited early human pharmacodynamic work
Endpoint
Growth hormone release and selectivity versus cortisol and prolactin
Route
Intravenous and subcutaneous
Quantity as reported
Reported in early pharmacology work; no established human protocol
Frequency
Varies

Result. Reported to release growth hormone with greater selectivity than earlier secretagogues in the models studied.

Adverse events. Not established in sustained human use.

Limitations. A pharmacodynamic signal is not a clinical outcome. No adequate long-term human outcome or safety data.

Pharmacology

Reported parameters

Half-life

2 hours

Roughly 2 hours as reported in early pharmacology work.

Visualise this half-life →

Routes studied

  • Subcutaneous
  • Intravenous

Evidence from one route does not transfer to another. Topical, oral, and injected administration can produce entirely different exposure from the same quantity.

Regulatory status

Not approved for human use. Included on FDA's list of substances raising significant safety risks for compounding purposes. Prohibited in sport.

Storage as documented

No approved labelling exists.

Safety

Signals reported in the literature

This lists what has been reported. It is not a complete safety profile, and for several compounds in this catalogue no systematic safety surveillance exists at all.

  • Long-term human safety is not established
  • Sustained elevation of GH/IGF-1 carries theoretical concerns regarding glucose regulation and tissue growth that are not resolved in the literature

Interactions

Register entries involving this compound

ipamorelininsulin

GH's counter-regulatory action on glucose is established physiology. Whether secretagogue-induced GH elevation is sufficient to matter clinically has not been studied.

Limitations. Mechanistic reasoning only. No interaction studies exist for this compound.

ipamorelincjc-1295

The premise is mechanistically coherent, but the specific combination has not been evaluated in an adequate human study. Commercial availability of a blend is not evidence.

Limitations. This is one of the most commonly assumed combinations in this category and one of the least supported by evidence.

Limitations

What the evidence cannot tell you

Given as much prominence as the findings, because for most compounds in this category it is the more important half.

  • A hormone-release signal is not a clinical outcome
  • No adequate long-term human outcome trials
  • Frequently sold blended with CJC-1295 despite the combination not being studied as such

Reference

Evidence grading key

AStrong

Multiple high-quality human trials, or strong systematic-review or meta-analytic evidence.

BModerate

Human controlled evidence exists, but replication or sample size is limited.

CPreliminary

Small human studies, observational evidence, or early-phase clinical work.

DPreclinical

Predominantly animal or in-vitro evidence. No adequate human outcome data.

EMechanistic

Biological plausibility or mechanistic reasoning without adequate outcome evidence.

XInsufficient / conflicting

Evidence is absent, irreconcilable, or too weak to support any directional statement.

Related

Other compounds studied in the same research areas