Ipamorelin 5/10 mg – Selective peptide GH-secretagogue

What is Ipamorelin?

Ipamorelin is a synthetic pentapeptide and a selective growth hormone secretagogue (GHRP) — an agonist of the ghrelin receptor (GHS-R1a). It mimics the action of ghrelin and stimulates the pituitary to the natural, pulsatile secretion of growth hormone (GH). In the literature it is described as "the first selective GH secretagogue", because it raises GH virtually without affecting other hormones.

It is precisely selectivity that is the most important feature of Ipamorelin. In contrast to older GHRP peptides such as GHRP-2, GHRP-6 or Hexarelin, Ipamorelin does not significantly increase the level of cortisol, prolactin or appetite. This makes it one of the cleanest and best-tolerated compounds of this class in studies.

Ipamorelin acts on the GHS-R1a receptor — distinct from the GHRH receptor targeted by analogs such as CJC-1295 or Sermorelin. Because these are two independent pathways, in studies they are classically combined into a pair (GHRH analog + Ipamorelin) for a synergistic effect — hence the ready-made complex CJC-1295 + Ipamorelin.

Ipamorelin is studied in the context of the GH/IGF-1 axis, regeneration, sleep, body composition and lipolysis. It is a research peptide — it holds no authorization as a medicinal product. See also the other recovery and anabolic peptides in our category.

In the version offered by Peptology, Ipamorelin is supplied as a lyophilized peptide with purity above 99% (HPLC/MS), confirmed by independent laboratory analysis (CoA for every batch). It is available in two vial formats — 5 mg and 10 mg — depending on the scale of the research protocol.

Available formats: 5 mg and 10 mg

Ipamorelin is available in two lyophilized formats that cover different scales of research work — from single in vitro series to longer GH-axis protocols with higher peptide consumption.

Both formats have identical purity > 99% and the same laboratory certificate for the batch. The choice of size depends on the scale of the protocol, not on the concentration of the active substance.

How Ipamorelin works — selective GHS-R1a agonism

In the research literature, Ipamorelin is described as a selective ghrelin receptor agonist that stimulates pulsatile GH secretion without disturbing the balance of other hormones. The three features below together explain its "clean" profile.

Why selectivity matters

Older GHRP secretagogues (GHRP-6, GHRP-2, Hexarelin) effectively raise GH, but at the same time activate pathways that increase cortisol, ACTH and prolactin, and some strongly stimulate appetite. Ipamorelin was designed to retain a strong effect on GH while eliminating these side effects — which is why it is described as the "cleanest" GHRP and is often chosen for the first research protocols.

Because the GHS-R1a (Ipamorelin) and GHRH (e.g. CJC-1295) pathways are independent, in studies a GHRH analog (background) is classically combined with Ipamorelin (pulse). This data comes from pharmacological studies and does not constitute a claim about the effect of the research-grade product.

Pharmacokinetics and pharmacodynamics of Ipamorelin

Ipamorelin is a small pentapeptide, which in the published pharmacokinetic data is described as a molecule with a moderate half-life and a fast, pulsatile profile of action on the GH axis.

• Biological half-life: about 2 hours
• GH peak: about 40 minutes after administration, returning to baseline within ~3 hours
• Target: the ghrelin receptor GHS-R1a in the pituitary
• Selectivity: no significant effect on cortisol, ACTH, prolactin and appetite
• Metabolism: breakdown by peptidases in plasma and tissues; without the involvement of hepatic CYP450
• Research schedule: subcutaneous (SC) administration, usually daily, often in combination with a GHRH analog

Ipamorelin vs GHRP-2 vs Hexarelin

The table below compares three GHRP secretagogues acting on the same GHS-R1a receptor, but differing in selectivity and profile. Ipamorelin stands out for its "clean" action on GH, GHRP-2 is stronger but less selective, and Hexarelin is the strongest but with the greatest effect on cortisol/prolactin and a risk of desensitization. The data are scientific and comparative in nature.

The values are approximate and come from the pharmacological literature on GH secretagogues. The table is scientific and comparative in nature and does not constitute a direct head-to-head comparison or a claim about the effect of the research-grade product.

Research and clinical data on Ipamorelin

Ipamorelin was developed as a pharmaceutical candidate, but its clinical program was not carried through to registration. It remains a research molecule with a well-described pharmacological profile. Below are the most important observations from the literature.

The first selective GH secretagogue

In pharmacological studies, Ipamorelin was characterized as the first secretagogue producing strong, dose-dependent GH secretion without a simultaneous increase in ACTH and cortisol — which distinguishes it from earlier GHRP peptides. This selectivity is its most frequently cited feature.

GH / IGF-1 profile

In observations, Ipamorelin produces a marked GH pulse (peak ~40 min) and — with repeated use — an increase in GH/IGF-1 axis markers. This profile is consistent with physiological, pulsatile GH secretion, rather than a constant, elevated background.

GHRH + GHRP synergy

In studies, the combination of Ipamorelin with a GHRH analog (like CJC-1295) is associated with stronger GH release than either component alone, because they act on separate receptors. A ready-made complex is available as CJC-1295 + Ipamorelin.

Note: The information is presented for scientific and informational purposes and is based on the pharmacological literature. It does not constitute medical advice, a recommendation for use or a claim about the effect of the research-grade product offered by Peptology.

Ipamorelin profile at a glance

• The first selective GH secretagogue — strong, pulsatile GH release via the GHS-R1a receptor
• Without an increase in cortisol, ACTH, prolactin and appetite — in contrast to GHRP-6, GHRP-2 and Hexarelin
• GH peak ~40 min, half-life ~2 h — a physiological, pulsatile profile
• Synergy with a GHRH analog (e.g. CJC-1295) — two separate receptors, GH amplification
• Very good tolerability — described as the "cleanest" peptide of the GHRP class
• Peptidase metabolism — without the involvement of hepatic CYP450

All information provided refers to the pharmacological literature on Ipamorelin and should not be interpreted as a promise of effect, an instruction for use or a claim about the effect of the research-grade product offered by Peptology.

Research dosing protocols

Due to its pulsatile profile, Ipamorelin is administered in studies subcutaneously, usually daily, often in combination with a GHRH analog:

• Subcutaneous (SC) administration, usually on an empty stomach — in the morning and/or before sleep (pulsatile models)
• Usually a daily schedule, due to the moderate half-life
• Combined schedules: GHRH analog (background) + Ipamorelin (pulse) for a synergistic effect
• Described as suitable for longer protocols thanks to good tolerability

In GH-axis protocols, Ipamorelin is classically combined with CJC-1295; a ready-made complex is CJC-1295 + Ipamorelin. These schedules come from the research literature and do not constitute a recommendation for self-administration.

Side effects and safety

Ipamorelin has one of the best safety profiles in the GHRP class. Side effects in observations are rare and mild, and the key advantage is the absence of an effect on cortisol, prolactin and appetite.

Thanks to its selectivity and good tolerability, Ipamorelin is described in the literature as suitable for longer protocols. Due to the GH-dependent mechanism, glucose handling remains an important element of observation. This information is scientific in nature and does not constitute an instruction for use.

Storage and reconstitution

Ipamorelin is supplied as a lyophilized (freeze-dried) powder in a vial. In lyophilized form the peptide is stable at room temperature, protected from light and moisture — refrigeration before reconstitution is not mandatory. After reconstitution, stability depends on the solvent used, with Peptide Matrix Water™ significantly extending the peptide's lifespan.

• Before reconstitution: room temperature, in the original packaging, protected from light and moisture. A refrigerator is not mandatory.
• After reconstitution with Peptide Matrix Water™: stability in the refrigerator +2 °C to +8 °C for up to 60 days under appropriate laboratory conditions — the stabilizing formula extends the peptide's lifespan relative to standard solvents.
• After reconstitution with bacteriostatic or sterile water: stability in the refrigerator +2 °C to +8 °C for up to 28 days under appropriate conditions. Do not refreeze the reconstituted solution.
• Reconstitution: in a laboratory setting, Peptide Matrix Water™, bacteriostatic water or sterile water for injection is usually used, depending on the protocol.
• Volume: maximum 3 mL of solvent (capacity of a standard vial). For a precise calculation of volume and units, use the peptide calculator.
• Homogenization: add the solvent slowly down the vial wall, without vigorous shaking — peptide bonds are sensitive to mechanical stress. Swirl gently, do not shake.

Laboratory tip: With your order, you can add Peptide Matrix Water™ to the cart — a stabilizing solution designed for working with reconstituted research peptides. More in the article Bacteriostatic water vs acetic acid vs matrix water.

Frequently asked questions about Ipamorelin

What exactly is Ipamorelin?

It is a synthetic pentapeptide and a selective ghrelin receptor agonist (GHS-R1a) that stimulates the pulsatile secretion of growth hormone from the pituitary. It stands out for not raising cortisol, prolactin or appetite. The results come from the pharmacological literature.

How does it differ from GHRP-2 and GHRP-6?

Ipamorelin raises GH with a minimal effect on cortisol and prolactin, whereas GHRP-2 and GHRP-6 also raise these hormones and more strongly stimulate appetite. That is why Ipamorelin is described as the most selective and best-tolerated in the GHRP class.

Can it be combined with CJC-1295?

Yes — this is the classic research schedule. The GHRH analog (CJC-1295) provides the background, and Ipamorelin adds the GH pulse; they act on different receptors, so the effect is additive. A ready-made complex is CJC-1295 + Ipamorelin.

What is Ipamorelin's half-life?

About 2 hours, with a GH peak ~40 minutes after administration and a return to baseline within ~3 hours. This justifies the daily, pulsatile administration schedule in protocols.

Which format to choose — 5 or 10 mg?

Both have identical purity > 99% and the same batch certificate. 5 mg works well for shorter protocols and single series, and 10 mg — for longer GH-axis studies and schedules combined with a GHRH analog.

How is Ipamorelin stored and reconstituted?

The lyophilized vial is stored at room temperature, protected from light and moisture. After reconstitution, stability depends on the solvent: with Peptide Matrix Water™ — up to 60 days in the refrigerator +2 °C to +8 °C; with bacteriostatic or sterile water — up to 28 days. Avoid refreezing.

Where to buy Ipamorelin for research?

Peptology offers Ipamorelin (5 / 10 mg) as a research peptide with confirmed purity above 99% (HPLC/MS) and independent laboratory analysis for every batch. Fast shipping, discreet packaging and certificates of purity with the product. For scientific background, also see the article Peptides — what they are, how they work, main categories and safety profile.

Related peptides in the Peptology catalog

Researchers working with Ipamorelin often also consider other GH-axis tools — GHRH analogs, GHRP secretagogues and ready-made complexes. Each of the products below has a certificate of purity above 99%:

See the full catalog: Recovery and anabolic peptides · Solutions for peptides · All peptides · Blog on peptide research

Laboratory reconstitution

Laboratory protocol — reconstitution, research protocols, storage

Standardized protocol applicable to all research peptides in the Peptology catalogue. To calculate the solution concentration (mg/mL) for each vial, use the peptide reconstitution calculator.

60-second protocol

Quick reference

What you need

Five rules for reconstitution

Calculating concentration

Storage

Four mistakes to avoid

Shipping information

🚚 Shipping information

• Products in our warehouse – orders placed by 15:00 on working days are dispatched the same day, later orders on the next working day.

• Delivery with GLS to your address in 3–5 working days.

• Shipping costs €5 and is free from €50.

Frequently Asked Questions (FAQ)

How does it differ from GHRP‑6 and -2?

Ipamorelin increases GH with minimal effect on cortisol and prolactin, whereas GHRP‑6/2 also affect those hormones.

In what form is Ipamorelin supplied and how should it be stored?

It is supplied as a lyophilized (freeze-dried) powder in a sealed vial. Store the unopened vial dry and protected from light, ideally at 2–8 °C. After laboratory reconstitution, keep the solution at 2–8 °C and use it within the period stated in the “Laboratory reconstitution” tab (up to 60 days with Peptide Matrix Water).

What purity does Ipamorelin have and how is it tested?

Every batch has a purity of 99% or higher, confirmed by HPLC and mass spectrometry (MS) and documented in a certificate of analysis (CoA). The report for the current batch is shown in the “Laboratory Analysis” tab.

Where can I buy Ipamorelin in Europe and what does it cost?

You can buy Ipamorelin in Europe online from Peptology, from 30,00 €. Delivery with GLS in 3–5 working days. Shipping is free from 50,00 €. Payment by card. Purity 99%+, with an HPLC report for every batch.

Laboratory Analysis

Ipamorelin - 5mg - Batch - 0226 - Purity

Ipamorelin - 10mg - Batch - 0226 - Purity