This page shows what was measured, who it was measured in, and what that does not settle.
What Ipamorelin does in the body
A growth hormone releaser designed to leave cortisol alone — never approved
The pituitary has two separate buttons for releasing growth hormone. One is pressed by the brain hormone GHRH; the other is pressed by ghrelin, the hunger hormone from the stomach. Ipamorelin presses the ghrelin button. Earlier drugs that did this also switched on the stress hormone axis and pushed up cortisol and prolactin, which made them unusable as medicines. Ipamorelin was built by stripping two amino acids out of an older compound, and the result released growth hormone just as strongly while leaving cortisol alone even at doses two hundred times higher than needed. In a person the effect is one sharp pulse of growth hormone that peaks at about forty minutes and is gone within hours.
What happened in people
Growth hormone release with EC50 1.3 nmol/L in rat pituitary cells and ED50 2.3 nmol/kg in conscious swine, comparable to GHRP-6
✎ Source-linked record
Where this came from
A person wrote this into the record with the study named beside it. No reviewer has signed it off.
The recorded finding that sits closest to something a person would notice. Written into the record, not signed off, and it carries no population or interval.
Phase 2 of ipamorelin for management of post-operative ileus, Helsinn Therapeutics — completed December 2009, no results posted (NCT00672074) · a recorded source, not a stored snapshot
The limit that matters most
That the cortisol selectivity measured in swine has been demonstrated in humans, where ACTH and cortisol were not reported endpoints
Where it acts
Growth hormone secretagogue receptor on anterior pituitary somatotrophs and in the hypothalamic arcuate nucleus
Kind of result
The kind of result is not recorded
Supervision
Professional supervision is normally required. It is a prescription or clinician-administered medicine where it is approved.
What the registries record it as
The substance registry classes this as chemical.
FDA substance registry · Y9M3S784Z6 · read 2026-08-29
Its recorded molecular formula is C38H49N9O5, weighing 711.9.
PubChem record · 9831659 · read 2026-08-29
Where each sentence above came from
No recorded sentence describes the change this makes in a way that stands on its own. The page opens with what it is taken for instead, and the recorded explanation follows below.
Shown as the opening line on this page.
A limit recorded against this substance. Not signed off as a reviewed claim.
The four opening statements run to 155 words.
Words this page uses
Four words worth knowing first
Chosen from what this page shows, with each one explained before the word it depends on.
Biomarker
A biomarker is a number from a test that stands in for something about health.
A picture of it, and where the picture fails
A biomarker is like a fuel gauge.
Where that stops being true. A gauge is wired to the tank. Many biomarkers are only loosely tied to health.
What people get wrong. A better number is read as a better life. Several medicines improved a number and helped nobody.
A measurable indicator used as a substitute for a clinical outcome of interest.
Placebo
A placebo is a dummy treatment given so the real one can be compared with it.
A picture of it, and where the picture fails
A placebo is like a blank control in an experiment.
Where that stops being true. A blank does nothing. People given a placebo often do get better.
What people get wrong. A placebo effect is read as imaginary. The improvement is measured and real.
An inactive intervention matched in appearance to the test intervention, used to control for non-specific effects.
Comparator
A comparator is whatever the treatment was measured against.
A picture of it, and where the picture fails
It is like the other runner in a race.
Where that stops being true. A race has one winner. A study can show both arms improved.
What people get wrong. Results are read without asking what the other group got. Beating nothing is not beating a treatment.
The control condition against which the experimental intervention is assessed.
What happened in people◇Read from sources, not yet reviewed
What happened in people
Each card is one study: the exact question it asked, who was in it, and whether it showed what it set out to show.
Ipamorelin and growth hormone concentrations, and pharmacokinetic parameters
✓ The study showed what it set out to show
Who was studied
Gobburu 1999 dose-escalation study in healthy male volunteers
How many people
40
Study design
Phase 1, five ascending 15-minute infusion rates, eight subjects per level
What this does not prove. Meeting one endpoint in one population does not carry to other goals or other people.
The limits of this study, and where it came from
Main limit. Between-subject variability in the pharmacodynamic parameters exceeded that in the pharmacokinetic parameters, so a given dose produced substantially different growth hormone responses across individuals.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Subcutaneous injection of a reconstituted lyophilised powder; intravenous infusion in the phase 1
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
Phase 2 of ipamorelin for management of post-operative ileus, Helsinn Therapeutics — completed December 2009, no results posted (NCT00672074) · a recorded source, not a stored snapshot
Phase 2 dose-finding study of ipamorelin for recovery of gastrointestinal function after bowel resection — completed May 2014, no results posted (NCT01280344) · a recorded source, not a stored snapshot
Phase 2 of ipamorelin for management of post-operative ileus, Helsinn Therapeutics — completed December 2009, no results posted (NCT00672074) · a recorded source, not a stored snapshot
Phase 2 dose-finding study of ipamorelin for recovery of gastrointestinal function after bowel resection — completed May 2014, no results posted (NCT01280344) · a recorded source, not a stored snapshot
Recovery of gastrointestinal function after small or large bowel resection
✗ The study did not show it
Who was studied
NCT01280344 — phase 2 dose-finding after bowel resection
Phase 2 of ipamorelin for management of post-operative ileus, Helsinn Therapeutics — completed December 2009, no results posted (NCT00672074) · a recorded source, not a stored snapshot
Phase 2 dose-finding study of ipamorelin for recovery of gastrointestinal function after bowel resection — completed May 2014, no results posted (NCT01280344) · a recorded source, not a stored snapshot
Growth hormone release potency and efficacy against GHRP-6 and GHRP-2, with ACTH, cortisol, prolactin, LH, FSH and TSH selectivity
✓ The study showed what it set out to show
Who was studied
Raun 1998 preclinical characterisation in rat and swine
How many people
0
Study design
Preclinical, primary pituitary cells, anaesthetised rats and conscious swine
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
EC50 1.3 +/- 0.4 nmol/L in rat pituitary cells; swine ED50 2.3 +/- 0.03 nmol/kg; no ACTH or cortisol release at over 200-fold the growth hormone ED50, where GHRP-6 and GHRP-2 raised both
Repeated elsewhere
Unreplicated
What this does not prove. Meeting one endpoint in one population does not carry to other goals or other people.
The limits of this study, and where it came from
Main limit. No limitation is recorded for this study.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Subcutaneous injection of a reconstituted lyophilised powder; intravenous infusion in the phase 1
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
Phase 2 of ipamorelin for management of post-operative ileus, Helsinn Therapeutics — completed December 2009, no results posted (NCT00672074) · a recorded source, not a stored snapshot
Phase 2 dose-finding study of ipamorelin for recovery of gastrointestinal function after bowel resection — completed May 2014, no results posted (NCT01280344) · a recorded source, not a stored snapshot
What we know
RNAWiki holds 4 written-up human studies for this substance, each with the question it asked.
How we know it
Each card names the study, the number of people and what the study set out to measure.
What this does not prove
These summaries were written by a person and have not been signed off as reviewed claims.
Why it matters
A study that failed is as informative as one that worked, and both are here.
What we still do not know
No reviewed claim exists, so no exact population, effect size or interval is published yet.
What happened in people◇Read from sources, not yet reviewed
How close this is to real life
The top step is something a person would feel or care about. The bottom is a guess from software. Filled steps are where evidence exists for this substance.
□Living longer, or avoiding a major eventNo evidence recorded. Death, a heart attack, a stroke, a hospital stay.No registered study measures this.
□What a body can do day to dayNo evidence recorded. Walking, dressing, breathing, recovering.No registered study measures this.
□Measured performanceNo evidence recorded. How much was lifted, how far was run, how fast.No registered study measures this.
□Symptoms and quality of lifeNo evidence recorded. Pain, tiredness, mood, sleep, as the person rated it.No registered study measures this.
□A number that stands in for healthNo evidence recorded. Cholesterol, blood sugar, bone density. A stand-in, not the thing itself.No registered study measures this.
■A step measured inside a personEvidence recorded. Something measured in human tissue or human cells.A human record sits on the stored organism ladder.
□AnimalsNo evidence recorded. Mice, rats, dogs. Useful for ideas, not proof about people.No animal record is stored.
■Cells in a dishEvidence recorded. Cells or chemistry on a bench, far from a whole body.Stored mechanism abstracts describe steps measured in cells or tissue.
□A guess from softwareNo evidence recorded. Nobody measured it. RNAWiki never publishes one as a finding.RNAWiki stores no prediction for this record. Software can suggest a link. RNAWiki does not publish one as a finding.
Higher on these steps means closer to something a person would feel. It does not mean better done.
What it changes in the body◇Read from sources, not yet reviewed
The path through the body
From what a person takes to what changes. A solid line is a step measured in people. A dashed line is a step nobody has measured that way.
Start
Ipamorelin
What a person takes: Subcutaneous injection of a reconstituted lyophilised powder; intravenous infusion in the phase 1.
The measurement behind this step
A lyophilised pentapeptide reconstituted before injection. The human characterisation used 15-minute intravenous infusions at 4.21 to 140.45 nmol/kg. Outside trials it is sold as a research-chemical vial for subcutaneous injection, typically alongside a GHRH analogue, with no assurance about stereochemical purity or endotoxin.
Getting in
Injected under the skin as a small peptide
Five amino acids in a vial of powder, reconstituted and injected. It reaches the bloodstream fast and leaves fast.
──Measured in people. Written by a person from the study named beside the step. Not signed off as a reviewed claim.
The measurement behind this step
Subcutaneous or intravenous administration. Human pharmacokinetics from a 15-minute intravenous infusion: dose-proportional exposure, terminal half-life 2 hours, clearance 0.078 L/h/kg, steady-state volume of distribution 0.22 L/kg. The C-terminal amide and the two D-residues protect against exopeptidase cleavage.
Phase 2 of ipamorelin for management of post-operative ileus, Helsinn Therapeutics — completed December 2009, no results posted (NCT00672074) · a recorded source, not a stored snapshot
Reaching the cell
Reaches the pituitary and the arcuate nucleus
Its target is on the outside surface of pituitary cells, so it does not need to get inside anything.
──Measured in people. Written by a person from the study named beside the step. Not signed off as a reviewed claim.
The measurement behind this step
The growth hormone secretagogue receptor 1a is a G protein-coupled receptor on the plasma membrane of anterior pituitary somatotrophs and on neurons of the hypothalamic arcuate nucleus. The circumventricular access of the pituitary to circulating peptides is why a small peripherally injected peptide can act there without crossing a tight blood-brain barrier.
Phase 2 of ipamorelin for management of post-operative ileus, Helsinn Therapeutics — completed December 2009, no results posted (NCT00672074) · a recorded source, not a stored snapshot
What it acts on
Presses the ghrelin button, not the GHRH button
It fits the receptor that the hunger hormone normally uses, which is a different receptor from the one the brain growth signal uses.
╌╌Measured in animals. A result in animals says what to test next. It does not say what happens in people.
The measurement behind this step
Agonism at GHSR1a couples through Gq to phospholipase C, inositol trisphosphate and intracellular calcium release. Antagonist profiling with GHRP and GHRH blockers assigned the effect to the GHRP-like receptor. EC50 in primary rat pituitary cells was 1.3 nmol/L, comparable to GHRP-6.
Phase 2 of ipamorelin for management of post-operative ileus, Helsinn Therapeutics — completed December 2009, no results posted (NCT00672074) · a recorded source, not a stored snapshot
The change it makes
One burst of growth hormone, and nothing else moves
Growth hormone comes out in a single pulse. Cortisol, prolactin and the reproductive hormones stay where they were.
──Measured in people. Written by a person from the study named beside the step. Not signed off as a reviewed claim.
The measurement behind this step
The human growth hormone response is a single episode peaking at 0.67 hours with exponential decline to negligible concentrations, modelled with a zero-order release rate over a finite duration. In swine, FSH, LH, prolactin and TSH were unaffected, and unlike GHRP-6 and GHRP-2 there was no ACTH or cortisol response even at more than 200 times the growth hormone ED50.
Phase 2 of ipamorelin for management of post-operative ileus, Helsinn Therapeutics — completed December 2009, no results posted (NCT00672074) · a recorded source, not a stored snapshot
What that does for a person
A clean pharmacology with nothing on the other end
The mechanism does what it says. Two phase 2 trials in surgical patients finished a decade ago and their results were never made public.
──Measured in people. Written by a person from the study named beside the step. Not signed off as a reviewed claim.
The measurement behind this step
Two completed phase 2 studies in post-operative gastrointestinal recovery, 117 and 320 patients, report no outcomes on the trial registry. No phase 3 was registered. Beyond growth hormone concentration, no human endpoint — body composition, IGF-1 over time, strength, recovery, sleep — has been published for ipamorelin.
Phase 2 of ipamorelin for management of post-operative ileus, Helsinn Therapeutics — completed December 2009, no results posted (NCT00672074) · a recorded source, not a stored snapshot
No suggested links are held for this record, so nothing is hidden from this path.
What we know
The record describes 5 steps from taking it to an effect in a person.
How we know it
Each step names the study behind it in the technical detail beside it.
What this does not prove
A change inside the body is a reason to look. It is not a result in a person.
Why it matters
A reader can see exactly where the chain stops being measured in people.
What we still do not know
No reviewed claim binds any of these steps to a named population.
What is missing or unclear◇Read from sources, not yet reviewed
Were people like you studied?
RNAWiki cannot tell whether a study fits you. It can show who was in it, and where the result stops carrying.
Who was studied
People similar to this profile were included.
In trials: healthy male volunteers in the phase 1, and patients recovering from small or large bowel resection in the two phase 2 studies. Outside trials: people injecting it, almost always paired with a GHRH analogue such as CJC-1295 or sermorelin.
Who is missing from the studies
Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.
Where the result stopped carrying
Both registered phase 2 trials completed without posting results, and no phase 3 followed either
Development for post-operative ileus, the only clinical indication ever pursued, was abandoned after the 320-patient dose-finding study
This is a scope explorer, not a diagnosis engine.
It shows who was studied so you can see whether people similar to you were included.
RNAWiki cannot tell whether a study fits you. It can show who was in it.
What it would be like to take◇Read from sources, not yet reviewed
Why it might seem to do nothing
A real effect and a noticed effect are different things. These are the recorded reasons the two come apart.
It was studied in different people
The people in the studies were not much like the reader.
On this record: Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.
The evidence may simply be wrong
Small early studies often do not hold up.
On this record: RNAWiki has not yet published a reviewed conclusion for this use.
Other reasons RNAWiki checked and found nothing for (11)
It was studied for a different goal
The studies measured something else entirely. Nothing in this record points to this reason.
A different form was studied
The studied form is not the form on the shelf. Nothing in this record points to this reason.
There was nothing to correct
Where a level is already normal, topping it up may change nothing. Nothing in this record points to this reason.
Something else had to happen too
In the studies it was paired with training, a diet or another treatment. Nothing in this record points to this reason.
The change is too small to feel
A real change can still sit below what a person notices. Nothing in this record points to this reason.
Day-to-day swing hides it
Sleep, food, stress and time of day move most numbers more than this would. Nothing in this record points to this reason.
Not enough time yet
The studies ran longer than the person has waited. Nothing in this record points to this reason.
It was not taken as studied
Missed days change the result, and studies count them. Nothing in this record points to this reason.
Something else changed at the same time
Two changes at once cannot be told apart afterwards. Nothing in this record points to this reason.
The product may not be what it says
Contents of a sold product are not always what the label states. Nothing in this record points to this reason.
No recorded reason
RNAWiki has nothing stored that would explain it. Nothing in this record points to this reason.
None of these is a reason to take more. Taking more is not a step this page ever suggests.
What it would be like to take◇Read from sources, not yet reviewed
What taking it involves
The recorded facts about getting hold of it and using it. Nothing here is a suggestion about what you should do.
How it is supplied
Still being tested
❝ Quoted from a source
Where this came from
Copied from a source RNAWiki stored, with the source named.
Read from the recorded approval status.
No source is stored against this line.
Form and route
Subcutaneous injection of a reconstituted lyophilised powder; intravenous infusion in the phase 1
✎ Source-linked record
Where this came from
A person wrote this into the record with the study named beside it. No reviewer has signed it off.
The form and route recorded on this substance.
No source is stored against this line.
Who oversees it
Professional supervision is normally required. It is a prescription or clinician-administered medicine where it is approved.
❝ Quoted from a source
Where this came from
Copied from a source RNAWiki stored, with the source named.
The identity record classes it as investigational; no register records an approval.
No source is stored against this line.
What is in the pack
A lyophilised pentapeptide reconstituted before injection. 45 nmol/kg. Outside trials it is sold as a research-chemical vial for subcutaneous injection, typically alongside a GHRH analogue, with no assurance about stereochemical purity or endotoxin.
✎ Source-linked record
Where this came from
A person wrote this into the record with the study named beside it. No reviewer has signed it off.
Recorded notes on how this is sold and what that means for what is in the pack.
No source is stored against this line.
Where it is registered
Regulatory records are listed in the technical disclosure at the foot of this page.
# Counted from records
Where this came from
A count of rows RNAWiki holds. It describes our records, not your body.
Register entries are stored per jurisdiction and shown with their dates.
No source is stored against this line.
Why people stop
Not recorded.
∅ Nothing recorded
Where this came from
RNAWiki holds nothing here and says so rather than guessing.
No record of why people stopped taking it is stored for this substance.
No source is stored against this line.
What it would be like to take◇Read from sources, not yet reviewed
What can go wrong
Sorted by where each line came from. A regulator's label and a report somebody sent in are not the same kind of fact.
·Worth asking a clinician aboutWritten into the record from the studies named on this page
The selectivity that defines the compound — no ACTH, cortisol, prolactin, LH, FSH or TSH response at over 200 times the growth hormone ED50 — was established in swine. In humans the reported phase 1 outcomes are pharmacokinetic and growth hormone concentrations; adverse events were not the focus. Two phase 2 trials in 437 surgical patients between them generated safety data that has never been published. What is known about chronic growth hormone secretagogue exposure comes from the ibutamoren literature, not from this compound.
Nobody counted how many people took this and were fine, so this cannot be turned into a rate.
Phase 2 of ipamorelin for management of post-operative ileus, Helsinn Therapeutics — completed December 2009, no results posted (NCT00672074) · a recorded source, not a stored snapshot
Over a long time. No completed tested study window is recorded, so long-term effects are not established by the registry record.
Groups the studies covered thinly. Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.
What is missing or unclear◇Read from sources, not yet reviewed
Does the exact form matter?
Evidence belongs to the exact thing that was tested. A different salt, a different mixture or a different preparation is a different question.
The form that was studied
Subcutaneous injection of a reconstituted lyophilised powder; intravenous infusion in the phase 1
✎ Source-linked record
Where this came from
A person wrote this into the record with the study named beside it. No reviewer has signed it off.
The form used in the studies cited on this page.
No source is stored against this line.
What is sold
45 nmol/kg. Outside trials it is sold as a research-chemical vial for subcutaneous injection, typically alongside a GHRH analogue, with no assurance about stereochemical purity or endotoxin.
✎ Source-linked record
Where this came from
A person wrote this into the record with the study named beside it. No reviewer has signed it off.
Recorded notes on which forms are sold and how they compare.
No source is stored against this line.
What is recorded as being sold
11 products list this as an active ingredient in the United States drug directory. 11 of them contain it and nothing else.
FDA National Drug Code directory · 84347-213 · read 2026-08-29
They are sold as powder.
FDA National Drug Code directory · 84347-213 · read 2026-08-29
Evidence carries across two names for one substance. It does not carry across a salt, a mirror form or a mixture.
What it would be like to take◇Read from sources, not yet reviewed
What you could measure
This one is decided with a clinician, so this section holds questions to ask rather than a plan to run.
Self-experiment planning is not offered for a prescription or clinician-supervised medicine, investigational agent. The questions below are for a clinician or pharmacist.
Questions worth asking
Which of the trials of Ipamorelin studied people like me?
What was measured, and for how long?
Was the result a laboratory value or a health outcome?
What would we watch for, and when would we stop?
Tracking can show whether something changed for you. It cannot show what caused it.
RNAWiki records evidence. It does not say whether this substance is right for you.
What is missing or unclear◇Read from sources, not yet reviewed
Claims that go past the evidence
Things said about this substance that sound reasonable, and the exact step that is missing between the evidence and the claim.
✗Goes past the evidence
That the cortisol selectivity measured in swine has been demonstrated in humans, where ACTH and cortisol were not reported endpoints
Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.
The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.
What would change this
A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.
RNAWiki has not yet published a reviewed conclusion for this use.
✗Goes past the evidence
That combining ipamorelin with CJC-1295 or sermorelin is safe or effective, which no human trial has examined
Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.
The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.
What would change this
A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.
RNAWiki has not yet published a reviewed conclusion for this use.
✗Goes past the evidence
That a single two-hour growth hormone pulse translates into sustained IGF-1 elevation or body composition change, neither of which has been measured for this compound
Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.
The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.
What would change this
A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.
RNAWiki has not yet published a reviewed conclusion for this use.
✗Goes past the evidence
That an unlicensed vial contains the correct stereoisomers; two of the five residues are D-amino acids and mass spectrometry alone cannot detect an all-L impurity
Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.
The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.
What would change this
A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.
RNAWiki has not yet published a reviewed conclusion for this use.
What is missing or unclear◇Read from sources, not yet reviewed
What nobody knows yet
Open questions, each with why it is open and what would close it.
How much did people take in the studies?
The sources RNAWiki checked hold nothing for this field.
Why it matters. A result belongs to an amount. Without the amount the result floats free.
What would answer it
A stored source that records it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
How fast does the body clear it?
The sources RNAWiki checked hold nothing for this field.
Why it matters. Without this, nothing on this page can say how long anything lasts.
What would answer it
A stored source that records it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
Missing populations
Which groups were under-represented in the studies has not been recorded.
Why it matters. Recorded by the evidence model as a gap on this record.
What would answer it
A study that measures it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
Missing long-term data
No completed tested study window is recorded.
Why it matters. Recorded by the evidence model as a gap on this record.
What would answer it
A study that measures it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
No reviewed conclusion
RNAWiki has not yet published a reviewed conclusion for this use.
Why it matters. Recorded by the evidence model as a gap on this record.
What would answer it
A study that measures it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
Missing interaction studies
No interaction was found in the registers checked. Not finding one is not the same as showing there is none.
Why it matters. Recorded by the evidence model as a gap on this record.
What would answer it
A study that measures it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
Formulation uncertainty
Several salts, forms or products of Ipamorelin are recorded. Results from one form may not transfer to another.
Why it matters. Recorded by the evidence model as a gap on this record.
What would answer it
A study that measures it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
Mechanism not reviewed
No reviewed mechanism story exists for this substance.
Why it matters. Recorded by the evidence model as a gap on this record.
What would answer it
A study that measures it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
What happened in people◇Read from sources, not yet reviewed
Check any of this yourself
Every line above traced back to the study it came from. This is the technical layer, and the vocabulary changes here.
Every line above can be traced to the study named beside it. Follow the link and read it.
It released growth hormone without touching ACTH or cortisol
In plain words
In pigs, ipamorelin released growth hormone as strongly as the older drugs in its class but, unlike them, did not raise ACTH or cortisol — even at doses more than two hundred times higher than needed.
What was measured
EC50, ED50 and Emax for growth hormone release, with parallel ACTH, cortisol, prolactin, LH, FSH and TSH measurements in rat and swine
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Raun et al. at Novo Nordisk characterised ipamorelin, a pentapeptide identified within a series lacking the central Ala-Trp dipeptide of GHRP-1. In primary rat pituitary cells it released growth hormone with EC50 1.3 +/- 0.4 nmol/L and Emax 85 +/- 5%, against 2.2 +/- 0.3 nmol/L and 100% for GHRP-6. In pentobarbital-anaesthetised rats, ED50 was 80 +/- 42 nmol/kg with Emax 1,545 +/- 250 ng/mL against 115 +/- 36 nmol/kg and 1,167 +/- 120 ng/mL for GHRP-6. In conscious swine, ED50 was 2.3 +/- 0.03 nmol/kg with Emax 65 +/- 0.2 ng/mL. No secretagogue tested affected FSH, LH, prolactin or TSH. GHRP-6 and GHRP-2 both raised ACTH and cortisol; ipamorelin did not, at doses more than 200-fold above its ED50 for growth hormone release. The authors describe it as the first GHRP-receptor agonist with selectivity for growth hormone comparable to GHRH itself.
Written into the record, not signed off as a reviewed claim
In humans: one pulse, peaking at 40 minutes, gone in hours
In plain words
A dose-escalation study in 40 healthy men found a two-hour half-life and a single burst of growth hormone peaking about forty minutes after infusion, falling back to negligible levels at every dose tested.
What was measured
Terminal half-life, clearance, volume of distribution, SC50 and maximal growth hormone production rate across five ascending infusion rates
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Gobburu et al. studied ipamorelin in healthy male volunteers at five infusion rates — 4.21, 14.02, 42.13, 84.27 and 140.45 nmol/kg over 15 minutes — with eight subjects at each level. Pharmacokinetics were dose-proportional with a terminal half-life of 2 hours, clearance of 0.078 L/h/kg and steady-state volume of distribution of 0.22 L/kg. The growth hormone response was a single episode peaking at 0.67 hours and declining exponentially to negligible concentrations at all doses. The concentration producing half-maximal growth hormone stimulation was 214 nmol/L and the maximal growth hormone production rate 694 mIU/L/h. Between-subject variability in the pharmacodynamic parameters exceeded that in the pharmacokinetic parameters, which is the practical reason a fixed dose produces very different responses in different people.
Written into the record, not signed off as a reviewed claim
Two completed phase 2 trials, no posted results, no third trial
In plain words
Helsinn ran ipamorelin in 117 and then 320 patients recovering from bowel surgery. Both trials completed. Neither posted results, and nothing followed.
What was measured
Registered phase 2 trials with a clinical endpoint: two, both completed, neither reported
Effect estimate
No reviewed effect estimate exists for this record.
Limits
This entry records a failure.
From the source
NCT00672074 was a phase 2, double-blind, placebo-controlled, multiple-dose study of ipamorelin versus placebo for the management of post-operative ileus, 117 participants, completed December 2009, primary endpoint recovery of gastrointestinal function, no results posted. NCT01280344 was a phase 2 double-blind placebo-controlled dose-finding study of ipamorelin versus placebo for recovery of gastrointestinal function in patients following small or large bowel resection, 320 participants, completed May 2014, same primary endpoint, no results posted. No phase 3 was registered and no product exists. The indication is worth noting: ghrelin-receptor agonism accelerates gastric emptying, so the clinical hypothesis was gut motility, not body composition.
Source
ClinicalTrials.gov records NCT00672074 (completed December 2009, n=117) and NCT01280344 (completed May 2014, n=320), Helsinn Therapeutics, neither with posted results
Role in the trial
Not matched to a registered study
Identity check
no open identity hold
Audit mark
verified
Review state
Written into the record, not signed off as a reviewed claim
Stacking with a GHRH analogue is the standard practice and is untested
In plain words
Ipamorelin is almost always injected alongside CJC-1295 or sermorelin on the theory that two switches beat one. No human study has tested that combination.
What was measured
That combining ipamorelin with a GHRH analogue is safe and effective over months of use, when no human trial of the combination exists
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
The physiological argument is sound as far as it goes: GHRH-receptor and ghrelin-receptor agonism act through separate pathways on the somatotroph, and co-administration of a GHRH analogue with a growth hormone secretagogue produces a larger growth hormone response than either alone. That is established for other pairs. It has never been studied for ipamorelin with CJC-1295 or with sermorelin in a registered human trial, at any dose, for any endpoint. What is being extrapolated is not only the pharmacodynamic sum but the safety of chronic combined stimulation, which is a different question again and one that no dataset addresses.
Written into the record, not signed off as a reviewed claim
The selectivity result is real and it is an animal result
In plain words
The famous claim that ipamorelin does not raise cortisol comes from rats and pigs. Human ACTH and cortisol were not the endpoint of the human study.
What was measured
ACTH and cortisol response to ipamorelin in conscious swine at over 200 times the growth hormone ED50
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Raun et al. measured ACTH and cortisol in conscious swine and found no significant elevation, at doses above 200-fold the growth hormone ED50 — a well-designed and unambiguous experiment in that species. The human study that followed characterised ipamorelin pharmacokinetics and the growth hormone response across five infusion rates; its reported outcomes are ipamorelin and growth hormone concentrations. This page states the selectivity finding where it was measured and does not upgrade it to a human result, because doing so is exactly the kind of substitution the audit exists to catch.
Written into the record, not signed off as a reviewed claim
Prohibited in sport, and detectable
In plain words
Growth hormone secretagogues are banned at all times in sport, and laboratory methods for finding them in blood and urine are published.
What was measured
Analytical detection of small peptide hormones and secretagogues in doping control blood and urine samples
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Ipamorelin belongs to the growth hormone secretagogue class prohibited at all times under WADA class S2, peptide hormones, growth factors, related substances and mimetics, alongside the GHRPs, the GHRH analogues and ibutamoren. Doping control methods for peptidic drugs in the 2-10 kDa range in blood, and immunopurification and nanoLC high-resolution mass spectrometry approaches for small peptide hormones, cover this class. Ipamorelin is at the small end of that range — 712 daltons — which makes it analytically closer to a small molecule than to the GHRH analogues, and correspondingly easier to confirm.
This order is fixed in code and does not count clicks or time on the page.
What is not here
6 questions this page could not answer
These sections were prepared and left out because there was nothing to put in them. They are listed rather than hidden, so the gaps in this record are visible.
What was measured, goal by goal — found nothing in the sources checked.
Felt, measured, or meaningful — found nothing in the sources checked.
How long anything takes — found nothing in the sources checked.
What it may clash with — found nothing in the sources checked.
Other ways to the same goal — found nothing in the sources checked.
What changed on this page — found nothing in the sources checked.
The record as stored
The full record, for auditing
Everything above is built from what is below. This layer keeps the technical vocabulary, record identifiers and every stored row, so a reader who wants to check the page can.
The older medicine-wide conclusion held in this record
Written for a clinical reader, and about the medicine as a whole rather than about one indication, population and set of trials. RNAWiki does not treat it as a programme conclusion and no reviewer has signed it off in that form. It is here word for word because it is what the record holds.
A pentapeptide ghrelin-receptor agonist that releases growth hormone as potently as GHRP-6 while leaving ACTH and cortisol untouched at 200 times the effective dose — a genuinely clean selectivity result in animals, followed by a two-hour half-life in humans, two silent phase 2 trials and no approval.
Recorded evidence blocks (5)
Q1
What did Ipamorelin's largest trial (320 people) and its longest (3.1 years) measure?
320 people in Ipamorelin's largest registered study, 3.1 years in its longest registered window, measuring Recovery of GI function. ClinicalTrials.gov · 2026-09-01
2 phase2; NCT01280344; 2014-05; no ageing endpoint recorded. Last human test completed 2014, NCT01280344.
Interpretation These counts include studies where Ipamorelin was a comparison treatment, a background treatment or an exposure in an observational study, and the longest window may be a planned end date. Trial roles have not yet been classified for this record.
Show the evidence
phase2
2
Last recorded human testNCT01280344
2014-05
recorded 2026-09-01 · last checked 2026-09-04
Q2
Ipamorelin was tested only in human — what did it show?
Interpretation Recovery of GI function — the recorded outcome words.
Show the evidence
humanNCT00672074
mechanism-only; Recovery of GI function; 2
recorded 2026-09-01 · last checked 2026-09-04
Q3
Which 2 trials of Ipamorelin posted no result?
Posted no result
2 of 2 completed trials
Registrations
NCT00672074 and NCT01280344
Completion dates
oldest 2009-12; newest 2014-05
Show the evidence
Trial
NCT00672074
2009-12
NCT01280344
2014-05
Q4
At the median, Ipamorelin's trials enrolled 218.5 people — anything larger?
Median enrolment
218.5
Largest enrolment
320
Registered trials counted
2
Q5
What is recorded about Ipamorelin and IGF-1?
"Wound-healing peptides such as BPC-157, TB-500, and GHK-Cu promote angiogenesis, integrin-mediated extracellular matrix remodeling, and fibroblast activation, whereas growth hormone secretagogues like ipamorelin, CJC-1295, tesamorelin, sermorelin, and AOD-9604 activate IGF-1 signaling and satellite cell repair." — where Ipamorelin and IGF-1 appear together. Europe PMC · pathway abstract search · 2026-01-02
IGF-1; PMID 41490200
Show the evidence
IGF-1PMID 41490200
"Wound-healing peptides such as BPC-157, TB-500, and GHK-Cu promote angiogenesis, integrin-mediated extracellular matrix remodeling, and fibroblast activation, whereas growth hormone secretagogues like ipamorelin, CJC-1295, tesamorelin, sermorelin, and AOD-9604 activate IGF-1 signaling and satellite cell repair."
recorded 2026-01-02 · last checked 2026-09-04
Where it is registeredIdentifiers, relations and other names
ClinicalTrials.gov — US Government work · Europe PMC — metadata only, under the recorded legal gate · derived from this page's own recorded fields; no external licence
✗ required summary fields resolved: 4 required field(s) not terminal: Why people use it, Best-supported result, Biggest unanswered question, Human evidence
✓ public claims reviewed: 0 reviewed claim(s); drafts are never rendered
✓ source coverage passed: 4 source rows
✓ no critical contamination: no quarantine open
✓ canonical metadata passed: slug and display name present
✓ no raw internal fields: enforced by the copy-contract test over the rendered page
This is a record of evidence. It is not medical advice, and it does not say this substance suits you. Nothing here says any substance on RNAWiki is appropriate for a child.