Ipamorelin Capsules UK
1 product from 1 brand · free UK delivery · EU 3–7 days
Last reviewed · prices and listings checked by Free Muscle
Ipamorelin (also written NNC 26-0161) is a synthetic pentapeptide growth hormone secretagogue, a five-amino-acid chain that acts as a selective agonist at the ghrelin receptor, GHS-R1a. It belongs to the growth hormone releasing peptide family alongside GHRP-6 and GHRP-2, and shares its receptor with the non-peptide compound MK-677. This page lists every brand of ipamorelin stocked at Free Muscle, compared on pack size, form and batch testing, and explains what the published research does and does not cover. Research use only, 18+.
What is ipamorelin?
Ipamorelin has the sequence Aib-His-D-2-Nal-D-Phe-Lys-NH2. It was identified in the 1990s from a chemistry programme that stripped the central Ala-Trp dipeptide out of the earlier growth hormone releasing peptide GHRP-1, and was first described in full in 1998. Like the other members of its family it binds the growth hormone secretagogue receptor on pituitary somatotrophs and triggers a pulse of growth hormone release. What set it apart in the original animal work was selectivity: unlike GHRP-6 and GHRP-2, it did not raise ACTH or cortisol, and it left FSH, LH, prolactin and TSH unchanged.
| Identifier | Ipamorelin |
|---|---|
| Development code | NNC 26-0161 |
| Sequence | Aib-His-D-2-Nal-D-Phe-Lys-NH2 (five residues) |
| Formula | C38H49N9O5 |
| Molecular weight | 711.9 g/mol |
| CAS number | 170851-70-4 |
| PubChem CID | 9831659 |
| InChIKey | NEHWBYHLYZGBNO-BVEPWEIPSA-N |
Formula, weight and identifiers are from PubChem, checked in October 2026.
Ipamorelin went into human pharmacokinetic studies and later into a phase 2 clinical trial for postoperative ileus, a slowing of the gut after bowel surgery. That trial did not meet its efficacy endpoints and development was discontinued. Ipamorelin has never been approved as a medicine anywhere. In the UK it is not a licensed medicine and not an authorised food supplement. It is also a peptide, which matters for a capsule product: peptides taken by mouth are largely broken down by digestive enzymes, which is why every human study of ipamorelin used intravenous infusion. Our article Do oral peptides actually work? covers that problem honestly.
What the published research reports
Raun and colleagues (1998) characterised ipamorelin in rat pituitary cells, anaesthetised rats and conscious pigs. It released growth hormone with a potency and efficacy similar to GHRP-6, and in pigs it did not raise ACTH or cortisol even at doses more than 200-fold above the level needed for half-maximal growth hormone release. This is the source of the compound's reputation for selectivity, and it is an animal study.
Gobburu and colleagues (1999) gave intravenous infusions of ipamorelin to healthy male volunteers, eight at each of five infusion rates. Pharmacokinetics were dose-proportional, with a terminal half-life of about two hours. Each infusion produced a single episode of growth hormone release, peaking at about 40 minutes and falling back to negligible levels; the variability of the growth hormone response between individuals was larger than the variability in pharmacokinetics.
Beck and colleagues (2014) ran a multicentre, double-blind, placebo-controlled phase 2 trial in 117 adults recovering from bowel resection. Intravenous ipamorelin given for up to seven days after surgery was described as well tolerated, but the median time to tolerating a first solid meal was 25.3 hours against 32.6 hours on placebo, a difference that was not statistically significant, and no secondary endpoint differed from placebo either.
Johansen and colleagues (1999) reported that ipamorelin, injected under the skin for 15 days, increased the rate of longitudinal bone growth in adult female rats without changing IGF-1 or blood markers of bone turnover, which is again an animal finding. None of these results is a claim about the capsules listed on this page. They describe injected peptide in animals and in supervised human studies, and the compound did not succeed in its one clinical trial. Our ipamorelin research guide covers these studies in more detail.
Brands of ipamorelin we stock
- Free Muscle Ipamorelin, Research Peptide: Free Muscle brand, capsule form, 60 capsules per bottle. Every batch is assayed for identity and purity by Janoshik Analytical, with the certificate sent on request. The listing states the declared peptide quantity per capsule where one is given; where it is not, we do not state a figure here.
This collection currently holds one listing. Any other brand of ipamorelin stocked in future would be listed here with its capsule count, declared quantity and batch-certificate status. Related peptides we stock are listed in the peptides collection.
How to compare them
Multiply the declared quantity per capsule by the number of capsules to get total peptide per bottle, then divide the listed price by that figure. Where a manufacturer does not declare a quantity per capsule, that calculation cannot be done and no honest cost per milligram exists; treat that as information in itself. Peptides also degrade more readily than small molecules, so the date and batch on the certificate matter more than they do for a compound like MK-677. See price per milligram for the method.
Batch testing and certificates of analysis
A Certificate of Analysis for a peptide batch should report identity, normally by HPLC and mass spectrometry confirming the expected molecular mass, and purity as a percentage, together with the batch number, test date and the laboratory that performed the work. Every Free Muscle batch is assayed by Janoshik Analytical, an independent laboratory; email us the batch number from your label with the product name and we send the certificate for that batch. For other brands we show a certificate only where the manufacturer supplies one for the batch we hold. A generic PDF without a batch number is not a batch certificate. For ipamorelin the identity result matters more than the purity figure: doping-control laboratories in Cologne and Oslo found Gly-ipamorelin, ipamorelin with one extra glycine at its N-terminus, in black-market growth products (Krug et al., 2018), and a high purity percentage alone does not show which of the two is present. Our lab tests page and the article How to read a COA explain the detail.
Where to buy ipamorelin in the UK: how to check a supplier
Whichever shop you buy ipamorelin from, check these five points before you order:
- A batch number and a certificate for that batch. The pack should carry a batch number, and the seller should be able to show a certificate of analysis for that same batch from a named laboratory, with the test date. Every Free Muscle-brand batch is assayed by Janoshik Analytical, and we send the certificate for your batch on request.
- The strength per capsule and the capsule count. With both figures you can work out the total milligrams in the pack and the price per milligram. If a listing does not state one of them, ask the seller before you order.
- Research-use labelling and an age check. A research compound should be sold for laboratory research use only, not for human consumption, to adults aged 18 or over, with no dosing or usage advice. That is how every listing here is sold.
- Prices in pounds sterling and tracked UK dispatch. UK delivery from us is free and tracked on every order, with no minimum spend, and usually arrives 2-3 working days after dispatch; orders placed before 2pm Monday to Friday are processed the same working day.
- A clear returns policy. Unopened items can be returned to us within 30 days.
Brand on this page: Free Muscle. The UK supplier checklist and how we test go into more detail.
Legal status in the UK
Ipamorelin is not a licensed medicine in the UK, holds no MHRA marketing authorisation and is not an authorised food supplement or novel food. It cannot be sold for human consumption, and Free Muscle supplies it for laboratory research only, to adults aged 18 or over. Under section S2 of the WADA Prohibited List, growth hormone secretagogues and growth hormone releasing peptides are prohibited at all times, so ipamorelin is incompatible with tested sport. For a wider look at how peptides differ from SARMs in UK law and in research, see SARMs vs Peptides.
Storage and handling
Peptides are less stable than small-molecule compounds. Keep the sealed bottle in a cool, dry place away from light and heat, and follow any storage instruction on the label. Reseal promptly after opening and do not transfer capsules to unlabelled containers. Record the batch number and date of receipt. Keep out of reach of children and pets and apply normal laboratory good practice.
Delivery and returns
Free Muscle is the trading name of FreeMuscle, a business registered in Andorra, with UK operations and dispatch in Scunthorpe. Orders ship with free tracked UK delivery in plain packaging, and orders placed before 2pm Monday to Friday are processed the same working day. EU delivery takes 3 to 7 working days. Unopened items can be returned within 30 days. See delivery and our 30-day guarantee.
Related reading
- Do Oral Peptides Actually Work? The Honest Answer
- SARMs vs Peptides: Choosing by Goal
- How to Read a Certificate of Analysis (COA)
- What Is Janoshik Analytical? Third-Party Testing Explained
References
- Raun K, et al. Ipamorelin, the first selective growth hormone secretagogue. Eur J Endocrinol. 1998;139(5):552-561. PMID: 9849822.
- Gobburu JV, et al. Pharmacokinetic-pharmacodynamic modeling of ipamorelin, a growth hormone releasing peptide, in human volunteers. Pharm Res. 1999;16(9):1412-1416. PMID: 10496658.
- Beck DE, et al. Prospective, randomized, controlled, proof-of-concept study of the Ghrelin mimetic ipamorelin for the management of postoperative ileus in bowel resection patients. Int J Colorectal Dis. 2014;29(12):1527-1534. PMID: 25331030.
- Johansen PB, et al. Ipamorelin, a new growth-hormone-releasing peptide, induces longitudinal bone growth in rats. Growth Horm IGF Res. 1999;9(2):106-113. PMID: 10373343.
- Krug O, et al. Analysis of new growth promoting black market products. Growth Horm IGF Res. 2018;41:1-6. PMID: 29864719.
- Semenistaya E, et al. Determination of growth hormone releasing peptides metabolites in human urine after nasal administration of GHRP-1, GHRP-2, GHRP-6, Hexarelin, and Ipamorelin. Drug Test Anal. 2015;7(10):919-925. PMID: 25869809.
- Teichman SL, et al. Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults. J Clin Endocrinol Metab. 2006;91(3):799-805. PMID: 16352683.
- Sigalos JT, Pastuszak AW. The Safety and Efficacy of Growth Hormone Secretagogues. Sex Med Rev. 2018;6(1):45-53. PMID: 28400207.
Last reviewed: October 2026.
Research compounds sold by Free Muscle are supplied for laboratory research use only and are not for human consumption. They are not authorised as medicines by the MHRA, EMA or FDA, are not food supplements, and are sold only to adults aged 18 or over. Nothing on this page is medical or dosing advice. Summaries of published research describe study findings and are not claims about any product.
Research guides
Frequently asked questions
Is ipamorelin legal in the UK?
Ipamorelin is not controlled under UK drugs law, yet it holds no medicines licence and is not an authorised food supplement, which rules out selling it for human consumption. Free Muscle supplies it as laboratory research material and will not sell it to anyone under 18. In sport, WADA lists it among the growth hormone releasing peptides, so it is prohibited.
Is ipamorelin a peptide or a SARM?
A peptide. Ipamorelin is a chain of five amino acids that acts at the ghrelin receptor to stimulate growth hormone release. SARMs are small molecules acting at the androgen receptor and have nothing in common with it pharmacologically. It is often sold beside SARMs, but it belongs to the growth hormone secretagogue class.
What is the difference between ipamorelin and MK-677?
Both act at the same receptor, GHS-R1a, but ipamorelin is a peptide with a half-life of about two hours in the human infusion study, while MK-677 is a non-peptide small molecule that is orally active and was studied in trials lasting up to two years. MK-677 has a much larger human literature. Ipamorelin's selectivity for growth hormone over cortisol comes from animal work.
Does ipamorelin work in capsule form?
We do not make that claim. Every published human study of ipamorelin used intravenous infusion, and peptides taken by mouth are largely broken down by digestive enzymes before they can be absorbed. Our capsules are supplied for laboratory research. Our article on oral peptides sets out the evidence on absorption without spin.
How do I verify the batch of ipamorelin I have?
The batch number is printed on the label. For Free Muscle brand ipamorelin, email it to us together with the product name and you will receive that batch's Janoshik Analytical certificate, covering identity and purity; make sure the certificate quotes the same batch number as your bottle. Other brands' listings show a certificate only if their manufacturer has provided one for the stock we hold.
Is ipamorelin detectable in anti-doping tests?
Section S2 of the WADA Prohibited List bans ipamorelin in and out of competition. A 2015 anti-doping study followed a single volunteer after nasal use: a metabolite, ipamorelin (1-4) free acid, remained detectable in urine once the parent peptide could no longer be found, and the authors noted that the detection window varies with individual metabolism, the formulation and the route of administration. Its short half-life does not make it undetectable, and anyone subject to anti-doping rules should treat it as a banned substance.
What is the difference between ipamorelin and CJC-1295?
They act at different receptors. Ipamorelin is a five-amino-acid peptide that stimulates the ghrelin receptor and had a terminal half-life of about two hours in the human infusion study. CJC-1295 is a modified growth hormone releasing hormone analogue that acts at the GHRH receptor and binds albumin; after injection under the skin in healthy adults its half-life was estimated at 5.8 to 8.1 days (Teichman 2006). Neither is a licensed medicine, and WADA section S2 prohibits both in sport.
What side effects were reported in ipamorelin research?
The only published trial in patients enrolled 117 adults after bowel surgery, who received ipamorelin or placebo intravenously for up to seven days. Adverse events emerging during treatment were recorded in 87.5 per cent of patients given ipamorelin and 94.8 per cent of those given placebo, and the authors described it as well tolerated. A review of the growth hormone secretagogue class pointed to the scarcity of long-term controlled studies, to concern about rising blood glucose and to the need for long-term safety data.
Where can I buy ipamorelin in the UK?
On this page you can compare every ipamorelin listing we stock (at present from Free Muscle). Every UK order ships free with tracking, with no minimum spend, and usually arrives 2-3 working days after dispatch. Everything here is supplied for laboratory research use only, not for human consumption, to adults aged 18 or over.
How fast is UK delivery?
UK delivery is free and tracked on every order, with no minimum spend, and usually arrives 2-3 working days after dispatch. Faster tracked UK delivery costs £6 and usually takes 1-2 working days. Orders placed before 2pm Monday to Friday are processed the same working day.
Do you deliver to Romania and the rest of the EU?
Yes. Orders to Romania and other EU countries travel by our paid, tracked international service and usually arrive 3-7 working days after dispatch; delivery to the rest of the world usually takes 5-14 working days. Prices are in pounds sterling (GBP). Rules differ in other countries, so check local law before ordering for delivery abroad.
Can I return an order?
Yes: unopened items can be returned within 30 days. Our guarantee page has the full policy.
Is there a discount when I buy more than one?
Yes, on Free Muscle-brand products: 5% off automatically when your cart holds 2 of them and 10% off with 3 or more, applied in the cart. The offers do not combine.