The Peptide Desk The Peptide Desk

This information is for research and educational purposes only. No medical recommendations. Products are not approved for human use. For health questions, consult a doctor.

Lexicon
Hormones & growth

Ipamorelin

A selective GH secretagogue. Triggers a GH pulse via the ghrelin receptor, in animal studies without the cortisol rise of older GHRPs.

4 min read 11 sources

To the product To the calculator
Ipamorelin vial with white powder and the black TPD label on a white podium, next to a long blue 3D peptide chain in a bright lab
Phase 2 · not approved

Summary

At a glance

Sources checked on 26 Oct 2026

Half-life
~2 hours

healthy men, infusion into a vein2

Until the GH peak
~40 minutes

a single pulse, then barely any GH left in the blood2

Without a cortisol rise
>200 -fold

this much more than the half-maximal GH amount, ACTH and cortisol stayed at GHRH level (pigs)1

Published phase 2 trial
117 people

after bowel surgery, well tolerated, no significant effect4

Phase 2 in the registry
2 trials

both completed, no phase 3, as of 26 Oct 202610

  • Ipamorelin is a pentapeptide that acts on the ghrelin receptor of the pituitary and so triggers a short pulse of growth hormone (GH).1
  • It is regarded as the first selective GH secretagogue: in pigs ACTH and cortisol rose no more than with GHRH, even at more than 200 times the half-maximal GH dose.1
  • In healthy men the half-life was about 2 hours. The GH peak came after around 40 minutes, then GH fell to very low levels.2
  • In a phase 2 trial with 117 people after bowel surgery ipamorelin was well tolerated but did not significantly shorten the time to the first meal.4
  • Ipamorelin is not approved, ChEMBL lists phase 2 as its highest phase. In mice it increased body fat and food intake. Everything here is the state of research, not a recommendation.113
Profile

Updated May 2026

Class
Selective GH secretagogue

ghrelin mimetic

Route
Subcutaneous
Frequency
1-3x per day

often before sleep

Form
Lyophilised powder

reconstituted with BAC water

Sizes
5 to 10 mg

2 sizes in the shop

Contents 16 sections
  1. At a glance
  2. What is Ipamorelin?
  3. How it works
  4. What you need
  5. Reconstitution
  6. Injection
  7. Dosing
  8. What the research shows
  9. Research status
  10. Side effects
  11. Practice
  12. Storage
  13. Related compounds
  14. FAQ
  15. Glossary
  16. Sources

What is Ipamorelin?

Ipamorelin is a short peptide that stimulates growth-hormone release by engaging the ghrelin receptor (unlike GHRH analogues such as CJC-1295, which act on the GHRH receptor). What is special: ipamorelin is considered selective. In pigs it triggered a GH pulse without raising ACTH or cortisol more than the body's own GHRH, unlike the older GHRP-2 and GHRP-6. It is not appetite-neutral, though: in animal studies ipamorelin increased food intake and body fat, according to a review less than GHRP-2 or GHRP-6. Neither has been studied in humans.

It is used subcutaneously, dosed in micrograms, often several times a day. It ships as a freeze-dried powder you dissolve in bacteriostatic water.

Comparison

Two routes to growth hormone

Which receptor at the pituitary is targeted, as described in the TPD lexicon. Tap a card to open its entry.

Ghrelin mimetic, selective Ipamorelin GHSR GHRH-R 1 of 2 receptors
Ghrelin mimetic GHRP-2 GHSR GHRH-R 1 of 2 receptors Ghrelin mimetic GHRP-6 GHSR GHRH-R 1 of 2 receptors GHRH analogue CJC-1295 without DAC GHSR GHRH-R 1 of 2 receptors GHRH analogue Tesamorelin GHSR GHRH-R 1 of 2 receptors Blend of both routes CP10 (CJC + IPA) GHSR GHRH-R 2 of 2 receptors

Simplified: ghrelin mimetics act on the ghrelin receptor, GHRH analogues on the GHRH receptor. There is no study on ipamorelin together with CJC-1295. 110

How it works

Ipamorelin mimics ghrelin and triggers a short GH pulse at the pituitary. In healthy men the peak came about 40 minutes after an intravenous infusion, after which GH fell back to very low levels. In animal studies, the cortisol rise that older GH secretagogues trigger did not occur.

Especially common is the combination with a GHRH analogue like CJC-1295: one provides the GHRH signal, the other the ghrelin stimulus. In humans such synergy has been shown for related compounds (GHRP-6 and ghrelin, each together with natural GHRH); there is no study of ipamorelin plus CJC-1295.

Where it acts

One receptor, several sites of action

Tap a point or a card. Colour = receptor, grey = observed. Almost all from animal studies.

  1. Pituitary

    Short GH pulse, ACTH and cortisol at GHRH level (pigs)1

    GHSR
  2. Stomach and gut

    After abdominal surgery faster gastric emptying and an earlier first bowel movement (rats)6

    GHSR
  3. Bone

    Lengthwise growth rose with the amount (rats)7

    Observed in trials
  4. Muscle

    Under cortisone muscle strength was better preserved (rats)9

    Observed in trials
  5. Fat tissue

    More body fat and food intake, independent of GH (mice)3

    Observed in trials

Known targets1

Compound CHEMBL58547: one described target, Agonist according to studies, no mechanism recorded in ChEMBL.

Ghrelin receptor (GHS-R1a)
Gene
GHSR
UniProt
Q92847
ChEMBL
CHEMBL4616
Action
Agonist according to studies, no mechanism recorded in ChEMBL
Two glass cells with cup-shaped receptors; blue molecule chains dock onto the front one and trigger a bright pulse of light while the rear cell stays calm
Symbolic image.

What you need

For subcutaneous use you need:

Supplies

5 things, numbered as in the picture

Tick off what you already have. Vial and BAC water are our real shop photos at the same size.

Ipamorelin vial and bacteriostatic water at the same size with the black TPD label, next to two U-100 insulin syringes, two alcohol swabs and a sharps container with a blue lid

  1. Ipamorelin vial

    The Ipamorelin vial with the freeze-dried powder

    In the shop

  2. Bacteriostatic water

    Bacteriostatic water to dissolve it

    In the shop

  3. U-100 insulin syringes

    U-100 insulin syringes

    Amazon (opens a new tab)

  4. Alcohol swabs

    Alcohol swabs for the vial cap and the skin

    Amazon (opens a new tab)

  5. Sharps container

    A sealable sharps container for used needles

As an Amazon associate we earn from qualifying purchases. Links open Amazon - no extra cost for you.

Reconstitution

The powder is dissolved in bacteriostatic water. How much water you add sets the concentration and therefore how many units you draw for your dose on the insulin syringe.

Use the peptide calculator for this: pick your vial size and the water volume to see the concentration and units per dose.

When dissolving, just add the bac water, it does not matter if it hits the powder directly. Then swirl or shake until everything has dissolved, both are fine.

Step by step

Dissolving the powder

Four steps, the same for every vial size.

  1. 1Wipe the cap

    Clean the rubber stopper with an alcohol swab.

  2. 2Add BAC water

    Just add it, it does not matter if it hits the powder directly.

  3. 3Swirl or shake

    Until everything has dissolved, both are fine.

  4. 4Draw up

    With the U-100 insulin syringe.

Less water higher concentration fewer units on the syringe Example: 5 mg + 2 ml = 2.5 mg/ml

Injection

The injection is subcutaneous, into the fat layer under the skin, classically the abdomen (keep clear of the area around the navel), the front and the inner side of the thigh or the back of the upper arm. Many place a dose before sleep, because the natural GH pulse comes in deep sleep anyway.

Injection

Where and at what angle

Pick a spot or switch the angle. Subcutaneous means: into the fat layer, not the muscle.

Rotate the spot each time, never the same one twice in a row.

90°More fat under the skin

Rule of thumb: where there is more fat under the skin, insert straight at 90 degrees. In lean people with little fat, 45 degrees, so the needle stays in the fat layer. Simplified diagram.

  1. Clean the spot with an alcohol swab and let it dry

  2. Pinch up a small fold of skin

  3. Insert the needle: at 90 degrees where there is more fat under the skin, at 45 degrees in lean people with little fat

  4. Inject slowly, wait a moment, then withdraw

  5. Put the needle straight into the sharps container

Rotate the site.

Dosing

Dosing

Dosing, titration and syringe

Loading the dosing information …

  • Getting started and stepping up, drawn as a staircase
  • Units on the U-100 syringe for every step
  • How long one vial lasts

What the research shows

Ipamorelin is the compound with which the concept of a selective GH secretagogue was described. The discovery and pharmacology work showed in pigs that it triggers a GH pulse without raising ACTH and cortisol more than GHRH. That sets it apart from GHRP-2 and GHRP-6; prolactin was unchanged with all compounds in that study. In humans there is a pharmacokinetic study in healthy men (half-life about two hours) and a phase 2 trial after bowel surgery, in which ipamorelin as an infusion for up to 7 days was well tolerated but did not significantly speed up bowel recovery. Ipamorelin is not an approved medicine.

The studies with links are in the source block below.

Study results

What the trials measured

Interactive: switch tabs, tap points, show or hide arms. Arms are named relative to each other, no dosing advice.

Time to the first tolerated meal4

Median in hours, phase 2, given into a vein for up to 7 days

First solid meal tolerated4 114 people analysed
Placebo 32.6 h
Ipamorelin 25.3 h

The difference was not significant (p = 0.15) and the further endpoints showed no difference to placebo either. A second phase 2 trial with 320 people has not published results.

Meal still in the stomach after 15 minutes6

Rats after abdominal surgery with bowel handling, share in percent

Left in the stomach6 less means faster emptying
After abdominal surgery without compound 78%
Ipamorelin 52%
Without surgery 44%

Ipamorelin brought gastric emptying after surgery close to animals without surgery. Animal model with one dose into a vein; in humans the effect on bowel recovery did not show.

Lengthwise growth of the shin bone7

Micrometres per day, adult female rats, 15 days under the skin

Growth per day7 three study amounts versus control
Without compound 42 µm
Lowest study amount 44 µm
Middle study amount 50 µm
Highest study amount 52 µm

Growth rose with the amount while IGF-1 in the blood stayed unchanged. A second study saw more bone mineral, but density per volume stayed the same: the bones grew larger, not denser.

Microscope with a Petri dish on the stage holding a piece of gut tissue, in a bright lab
Symbolic image.

Research status

Where the research stands

Registered trials with ipamorelin: two phase 2 trials on bowel recovery after surgery, both completed. As of 26 Oct 2026.

  1. Preclinical GH release in cells, rats and pigs
  2. Phase 1 no registered trial
  3. Phase 2 2 trials, 2 completed
  4. Phase 3 no registered trial
  5. Approval not yet
Not approved. ChEMBL lists ipamorelin with phase 2 as the highest phase, without an approval year.10
Show all 2 phase 2 trials on a timelineHide timeline 2 completed 0 running 1 with results
Phase 2

Bar: start to primary endpoint (planned for running trials). Green = completed, blue = progress until 26 Oct 2026.

Side effects

Human data on side effects come only from the phase 2 trial (intravenous infusion, up to 7 days): there, adverse events were not more frequent with ipamorelin than with placebo. Studies on longer subcutaneous use are lacking. Described as effects of GH or the compound class are water retention, tingling in the hands and higher blood sugar. In animal studies, ipamorelin also increased food intake, weight and body fat.

Tolerability

Tolerability in the phase 2 trial

Phase 2 after bowel surgery, given into a vein for up to 7 days. The only published human data over several days.

95 of 100 Placebo
88 of 100 Ipamorelin
Event PlaceboIpamorelin
At least one adverse event4 95%88%

Adverse events are common after bowel surgery, hence the high values in both groups. There is no study on giving it under the skin for weeks.4

Practice

  1. Often combined with CJC-1295

    A stronger GH output has not been shown in studies for this exact combination.

  2. Dosing before sleep uses the natural GH rhythm.

  3. Inject with some gap from large, carb-heavy meals.

Bed with a light blue sleep mask on the pillow, a glass of water on the bedside table and moonlight outside the window

Storage

The undissolved powder is robust, normal room temperature (around 20 to 25 degrees) is fine, ideally kept in the dark. The reconstituted solution goes into the fridge (2 to 8 degrees) and stays stable there for at least 4 to 6 months with barely any loss of potency, in practice considerably longer. The bacteriostatic water brings a preservative that keeps the dissolved form stable for longer.

Shelf life

How long it keeps

Undissolved (powder) Room temperature, around 20 to 25 degrees, dark

Robust, no fridge needed. Keeps for several months without trouble.

Dissolved (mixed) Fridge, 2 to 8 degrees

At least 4 to 6 months with barely any loss of potency. The bacteriostatic water brings a preservative.

  • Keep it dark
  • Dissolved: 2 to 8 degrees
  • Note the mixing date on the vial
Nine vials with white powder and blue caps in the door shelf of a bright fridge
Powder dark at room temperature, once dissolved into the fridge (2 to 8 degrees), stable there for at least 4 to 6 months. Symbolic image.

Related

Related compounds

Same receptors, blends with Ipamorelin or a different path: all in the TPD lexicon.

Ipamorelin
CP10 (CJC + IPA) Contains ipamorelin plus CJC-1295 Tesa + Ipa Blend Contains ipamorelin plus tesamorelin GHRP-2 Same receptor, according to a study also raises ACTH and cortisol GHRP-6 Same receptor, older GH secretagogue Hexarelin Same receptor MK-677 (Ibutamoren) Same receptor, as a tablet CJC-1295 without DAC Other route: GHRH receptor Tesamorelin Other route: GHRH receptor HGH 191AA (Somatropin) Growth hormone itself instead of a trigger

FAQ

Common questions about Ipamorelin

Short answers, each backed by the sources below.

Is ipamorelin approved?

No. ChEMBL lists ipamorelin with phase 2 as the highest phase. ClinicalTrials.gov lists two phase 2 trials on bowel recovery after surgery, both completed. There is no approval trial (phase 3).1110

What does selective mean for ipamorelin?

In the discovery study in pigs ipamorelin released GH without raising ACTH and cortisol more than the body's own GHRH, even at more than 200 times the amount. GHRP-2 and GHRP-6 raised both. FSH, LH, prolactin and TSH stayed unchanged with all tested compounds.1

How long does one dose act?

In healthy men the half-life was about 2 hours. After an infusion into a vein a single GH pulse followed with its peak after around 40 minutes, then GH fell to very low levels. With rising amounts the GH response only increased up to a saturation point.2

What did the human trial show?

The published phase 2 trial with 117 people after bowel surgery found no significant difference: patients tolerated their first meal after a median of 25.3 instead of 32.6 hours (p = 0.15). Ipamorelin was well tolerated. The second phase 2 trial with 320 people has not published results.410

Does ipamorelin cause hunger or fat gain?

In mice ipamorelin increased food intake, leptin and the share of body fat, even in animals without growth hormone. In rats after surgery food intake rose with repeated dosing. Neither has been studied in humans.35

What is known about bone and muscle?

In adult rats lengthwise bone growth rose with the amount. Another study saw more bone mineral but the same density per volume, so the bones grew larger. Under cortisone muscle strength and bone formation were better preserved in rats. There are no human studies on this.789

Glossary

Terms explained briefly

Dotted words in the text open these explanations directly.

ACTH
A pituitary hormone that stimulates the adrenal gland to release cortisol.
Cortisol
A stress hormone of the adrenal gland. Raised for long periods it breaks down muscle and bone.
GH secretagogue
A compound that makes the body release its own growth hormone instead of supplying it from outside.
Ghrelin
A hormone from the stomach that triggers hunger and stimulates GH release at the pituitary. Ipamorelin mimics it at the ghrelin receptor.
GHRH
Growth hormone-releasing hormone from the hypothalamus. It acts via its own receptor; CJC-1295 and tesamorelin mimic it.
Half-life
The time after which only half of a compound is left in the blood.
Lyophilisate
Freeze-dried powder. Without water a peptide keeps much longer.
Pentapeptide
A chain of five amino acids. In ipamorelin some are modified building blocks that slow breakdown.
Postoperative ileus
A temporary standstill of bowel movement after abdominal surgery. Ipamorelin was tested for this in phase 2.
Subcutaneous
Into the fat layer just under the skin.
Trial phases
Phase 1 tests tolerability in a few people, phase 2 effect and dose in a few hundred, phase 3 confirms benefit and safety in thousands.

Evidence

Sources

Show all 11 sourcesHide sources 9 Studies1 Trial registry1 Database checked 26 Oct 2026

Studies

  1. Discovery and pharmacology of ipamorelin (cells, rats, pigs)

    Raun et al., European Journal of Endocrinology, 1998

    DOI 10.1530/eje.0.1390552 PMID 9849822
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  2. Uptake, clearance and GH response in healthy men

    Gobburu et al., Pharmaceutical Research, 1999

    DOI 10.1023/A:1018955126402 PMID 10496658
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  3. More body fat with GH secretagogues, independent of GH (mice)

    Lall et al., Biochemical and Biophysical Research Communications, 2001

    DOI 10.1006/bbrc.2000.4065 PMID 11162489
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  4. Phase 2 trial after bowel resection

    Beck et al., International Journal of Colorectal Disease, 2014

    DOI 10.1007/s00384-014-2030-8 PMID 25331030 NCT00672074
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  5. Ipamorelin in bowel paralysis after surgery (rats)

    Venkova et al., Journal of Pharmacology and Experimental Therapeutics, 2009

    DOI 10.1124/jpet.108.149211 PMID 19289567
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  6. Gastric emptying after abdominal surgery (rats)

    Greenwood-Van Meerveld et al., Journal of Experimental Pharmacology, 2012

    DOI 10.2147/JEP.S35396 PMID 27186127
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  7. Lengthwise bone growth (rats)

    Johansen et al., Growth Hormone & IGF Research, 1999

    DOI 10.1054/ghir.1999.9998 PMID 10373343
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  8. Bone mineral with ipamorelin and GHRP-6 (rats)

    Svensson et al., Journal of Endocrinology, 2000

    DOI 10.1677/joe.0.1650569 PMID 10828840
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  9. Ipamorelin against breakdown under cortisone (rats)

    Andersen et al., Growth Hormone & IGF Research, 2001

    DOI 10.1054/ghir.2001.0239 PMID 11735244
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed

Trial registry

  1. Trials with ipamorelin on ClinicalTrials.gov

    ClinicalTrials.gov, U.S. National Library of Medicine

    Checked 26 Oct 2026 via ClinicalTrials.gov API v2

Database

  1. Ipamorelin in ChEMBL (highest phase 2)

    ChEMBL, EMBL-EBI (CHEMBL58547)

    Checked 26 Oct 2026 via ChEMBL

In the shop

Ipamorelin in the catalog

Sizes, prices and shipping times are on the product page.

To the product