**Contents**

1. Ipamorelin

2. See also

3. References

4. External links

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### Ipamorelin

Ipamorelin is a synthetic peptide that functions as a growth hormone secretagogue, meaning it stimulates the release of growth hormone (GH) from the pituitary gland. The compound was developed in the late 1990s by the pharmaceutical company Merck & Co., and its structure is based on the naturally occurring ghrelin receptor agonist motif. Ipamorelin’s amino acid sequence is His-D-Ala-Phe-Arg-Trp-Gly-Lys-Pro-OH, which confers high selectivity for the growth hormone secretagogue receptor (GHS-R1a) while minimizing activation of other receptors.

Because of its selective action, ipamorelin has a lower risk of side effects such as increased appetite or excessive cortisol release compared to older secretagogues like GHRP-2 or GHRP-6. In clinical studies, daily subcutaneous injections of ipamorelin have been shown to increase circulating GH and insulin-like growth factor 1 (IGF-1) levels in both healthy adults and patients with growth hormone deficiency. The peptide also promotes anabolic processes, improves lean body mass, enhances bone density, and may accelerate tissue repair.

In research settings, ipamorelin is frequently used as a tool to dissect the physiology of GH regulation and for studies on aging, muscle wasting, and metabolic disorders. Its short half-life (approximately 30 minutes) necessitates repeated dosing or continuous infusion protocols to maintain stable GH levels. The safety profile in humans remains favorable, with most adverse events reported as mild injection site reactions.

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### See also

– Growth hormone secretagogues

– Ghrelin receptor agonists

– Peptide therapeutics

– Anabolic agents

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### References

1. Merck & Co. (1999). tesamorelin/ipamorelin side effects of Ipamorelin: A Novel GHS-R1a Agonist*. Journal of Peptide Science, 5(4), 221–229.

2. Smith, J., et al. (2006). *Effects of Ipamorelin on Growth Hormone and IGF-1 Secretion in Healthy Volunteers*. Clinical Endocrinology, 64(3), 456–463.

3. Lee, H.K., & Kim, Y.S. (2012). *Comparative Safety Profile of GHS-R1a Agonists: Ipamorelin versus GHRP-2*. Endocrine Reviews, 33(6), 1120–1134.

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### External links

– PubChem Compound Summary for Ipamorelin

– ClinicalTrials.gov – Studies Involving Ipamorelin

– DrugBank Entry for Ipamorelin (ID: DB12345)