Ipamorelin is a synthetic pentapeptide that stimulates the pituitary to release growth hormone (GH). Since its discovery in 1998, it has gained a lot of attention as the first selective GH secretagogue.
It stimulates GH release without affecting other pituitary hormones such as adrenocorticotropic hormone, follicle-stimulating hormone, luteinizing hormone, thyroid-stimulating hormone, and prolactin.
Ipamorelin has primarily been researched preclinically for muscle gain and weight loss, as well as for counteracting corticosteroid side effects and postoperative complications [1].
Ipamorelin has an intriguing mechanism of action that mimics some aspects of ghrelin (hunger hormone). It’s a selective agonist, which activates the ghrelin receptor pathway [2]. This interaction activates GH release from the pituitary gland, essentially initiating anabolic processes, including:
In rodents, ipamorelin increases appetite, hunger, and caloric intake, suggesting that it may be helpful in patients with cachexia or other conditions where weight gain is beneficial [3]. However, in humans, its effect on appetite appears to vary between individuals.
Ipamorelin-induced GH may act on muscles through insulin-like growth factor-1 (IGF-1) to increase muscle protein synthesis, inhibit protein degradation, stimulate satellite cell activity, and counteract myostatin signals [4].
In rats treated with glucocorticoid (GC), ipamorelin significantly increased maximum muscle tension and the rate of periosteal bone formation by fourfold [5].
These findings suggest that ipamorelin may mitigate the decline in muscle strength and bone formation typically observed in GC-treated rats.
In young rats, chronic administration of ipamorelin does not lead to desensitization of the GH response, helping to increase body weight.
However, chronic administration of ipamorelin on pituitary cell culture did lead to a dampened GH response over time, suggesting a desensitization response [6].
GH is essential for linear body growth during childhood, bone remodeling throughout life, and bone preservation in aging adults. GH and its downstream effector IGF-1 are central to skeletal growth and homeostasis. They activate osteoblasts and increase calcium storage and bone collagen.
In adult rats, 12 weeks of continuously administered ipamorelin significantly increased body weight, bone mineral content, and femur and vertebra L6 bone volume [6].
Another rat study found that ipamorelin increased linear growth rate and body weight in a dose-dependent manner. However, the ipamorelin treatment did not alter levels of IGF-1, IGFBPs, or serum markers of bone formation or resorption [7].
The effect of ipamorelin on weight has been paradoxical. Although GH is a crucial hormone for weight loss, most rodent studies found that ipamorelin assists with weight and body fat gain.
Ipamorelin has been shown to exert effects beyond muscle mass regulation. Experimental studies demonstrated that it significantly increased insulin secretion (p < 0.04) from the pancreas in both normal and diabetic rats.
These findings suggest that ipamorelin may influence glucose metabolism and insulin-dependent anabolic processes [8].
Ipamorelin demonstrated gastrointestinal effects that are mediated through activating ghrelin receptors. In a rodent model of postoperative ileus, a painful bowel paralysis after surgery, ipamorelin was shown to accelerate gastric emptying by enhancing gastric contractility [9].
A clinical trial on 114 patients who had undergone bowel resection surgery compared twice-daily ipamorelin administration with placebo to assess its effects on shortening the time to the first solid meal.
Although there was no statistically significant difference between ipamorelin and the placebo, no safety concerns were observed [10].
In a Phase 2 placebo-controlled trial, ipamorelin had lower but nonsignificant differences in incidents of side effects than placebo (87.5% in the ipamorelin group vs. 94.8% in the placebo group) [10].
Adverse effects observed in this trial included headache, gastrointestinal symptoms, and injection site reactions. The study did not report severe side effects specific to ipamorelin. The one report of risk for immunogenicity was linked to a production-related impurity in an IV administration [11].
Research Use Only. All findings described above are derived from preclinical studies (animal models and in vitro experiments). Ipamorelin is not approved by the FDA for any diagnostic or therapeutic use in humans. Genesis Peptides makes no claims regarding human clinical efficacy. This product is sold exclusively for laboratory research.
Every lot undergoes five independent assays before release. Results are published in the lot-specific Certificate of Analysis.
Every lot undergoes our 4-panel testing protocol: HPLC purity analysis, ESI-MS identity confirmation, LAL endotoxin screening, and amino acid analysis (for peptides >15 residues). Full analytical data is published in the Certificate of Analysis for each lot.
Lyophilized peptides should be stored at -20°C or below for long-term stability. Once reconstituted, peptides should be stored at 2–8°C and used within a reasonable timeframe depending on the specific compound. Avoid repeated freeze-thaw cycles. Always store in a dry environment away from direct light.
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No. All compounds sold by Genesis Peptides are strictly for in vitro and preclinical laboratory research purposes only. They are not approved for human consumption, therapeutic use, or diagnostic purposes. By purchasing, you confirm the products will be used solely for legitimate research applications.
A Certificate of Analysis (COA) is a document issued by our analytical laboratory that reports the results of all quality control tests performed on a specific lot of product. Each COA includes HPLC chromatograms, mass spectra, endotoxin results, and amino acid analysis where applicable. COAs are available in our COA Library for every lot we have shipped.
Yes. We offer volume pricing for universities, research institutions, and laboratories with recurring needs. Discounts begin at 10+ units and scale with volume. Contact our team for a custom quote tailored to your research requirements.
FOR RESEARCH USE ONLY — Products are sold exclusively for in vitro and preclinical laboratory research. Not for human consumption or administration. Not intended for diagnostic or therapeutic use. These statements have not been evaluated by the FDA.