Comparison

Ipamorelin vs. Sermorelin

Two peptides side-by-side — identity, evidence base, legal status and known adverse events.

Identity

Mechanism of action

Ipamorelin

Ipamorelin is a selective agonist at the GH secretagogue receptor (GHSR-1a). Compared to GHRP-2 and GHRP-6 its selectivity for the growth-hormone axis is higher; ACTH, cortisol and prolactin are not significantly stimulated in clinical studies. This selectivity was the main reason for its development over older GHRPs.

Sermorelin

Synthetic analogue of the first 29 amino acids of human growth-hormone-releasing hormone (GHRH). Stimulates pulsatile endogenous growth-hormone secretion from the pituitary via the GHRH receptor. Very short plasma half-life — pharmacodynamic effect lasts several hours nevertheless.

Evidence base

Highest evidence

Human RCT

Studies

of which in humans

Effects recorded

Open conflicts

Documented adverse events

Legal status

Country	Ipamorelin	Sermorelin
Germany	Unapproved	Unapproved
United States	Unapproved	Research only

Full entries

Frequently asked questions

What is the difference between Ipamorelin and Sermorelin?: Ipamorelin is classified as "Growth", while Sermorelin is classified as "Growth". Ipamorelin: Synthetic pentapeptide and selective growth-hormone secretagogue. Developed at Novo Nordisk in the 1990s as a pentapeptide GHRP successor; clinical development was discontinued after phase 2 (post-operative ileus). Sermorelin: Synthetic analogue of the first 29 amino acids of human GHRH. Stimulates pulsatile growth-hormone secretion from the pituitary. Formerly FDA-approved as Geref Diagnostic, now withdrawn in many markets — compounding and research use dominate. This page contrasts both neutrally and source-based — with no usage or dosing recommendation.
Which peptide is better supported by science, Ipamorelin or Sermorelin?: The highest available evidence level is "Human RCT" for Ipamorelin and "Human RCT" for Sermorelin. A higher evidence level means more robust data, but says nothing about suitability for an individual. The full body of evidence is on each peptide's own page.
What is the legal status of Ipamorelin and Sermorelin in Germany and the United States?: Germany: Ipamorelin — Unapproved, Sermorelin — Unapproved. United States: Ipamorelin — Unapproved, Sermorelin — Research only. These are factual summaries with source and review date on the individual pages.

Country

Ipamorelin

Sermorelin

Germany

Unapproved

United States

Unapproved

Research only

Frequently asked questions

What is the difference between Ipamorelin and Sermorelin?

Ipamorelin is classified as "Growth", while Sermorelin is classified as "Growth". Ipamorelin: Synthetic pentapeptide and selective growth-hormone secretagogue. Developed at Novo Nordisk in the 1990s as a pentapeptide GHRP successor; clinical development was discontinued after phase 2 (post-operative ileus). Sermorelin: Synthetic analogue of the first 29 amino acids of human GHRH. Stimulates pulsatile growth-hormone secretion from the pituitary. Formerly FDA-approved as Geref Diagnostic, now withdrawn in many markets — compounding and research use dominate. This page contrasts both neutrally and source-based — with no usage or dosing recommendation.

Which peptide is better supported by science, Ipamorelin or Sermorelin?

The highest available evidence level is "Human RCT" for Ipamorelin and "Human RCT" for Sermorelin. A higher evidence level means more robust data, but says nothing about suitability for an individual. The full body of evidence is on each peptide's own page.

What is the legal status of Ipamorelin and Sermorelin in Germany and the United States?

Germany: Ipamorelin — Unapproved, Sermorelin — Unapproved. United States: Ipamorelin — Unapproved, Sermorelin — Research only. These are factual summaries with source and review date on the individual pages.