Sermorelin (GHRH 1-29) Research Peptide

What Is Sermorelin?

Sermorelin is a shortened, synthetic version of growth hormone-releasing hormone, the hypothalamic hormone that signals the pituitary gland to release growth hormone. Natural human GHRH has 44 amino acids. Research in the early 1980s showed that the first 29 carry its full receptor-binding activity, and sermorelin is that 29-residue fragment with an amidated C-terminus. Its single sulfur atom comes from the methionine at position 27.

Sermorelin has a well-documented pharmaceutical history. It was approved by the FDA under the brand name Geref, used for growth hormone deficiency in children, and studied for diagnostic testing of pituitary function. The manufacturer stopped production in 2008 for business reasons, not safety concerns. That history left sermorelin with a deeper base of published human pharmacology than most research peptides, covering pulsatile growth hormone release and IGF-1 levels.

Because sermorelin stimulates the pituitary to release its own growth hormone rather than supplying growth hormone directly, it is widely used as a reference compound for upstream GH-axis research. It is the unmodified sequence, so the enzyme DPP-IV breaks it down quickly; longer-lasting analogs were built to fix that. See Sermorelin vs Tesamorelin and CJC-1295 DAC vs no DAC.

This product is strictly for research purposes only. Not approved for human or animal use.

Key Characteristics

Molecular Profile

Physical Properties

Sermorelin in Published Research

Because sermorelin was an approved drug, more human pharmacology data exists for it than for most GH-axis research peptides. Approval-era studies documented increases in growth hormone pulsatility and IGF-1, and its use as a diagnostic test for pituitary growth hormone reserve in children and adults. Later research examined sermorelin in age-related growth hormone decline and sleep architecture.

Mechanistically, sermorelin binds the GHRH receptor on somatotroph cells of the anterior pituitary. That places it upstream of growth hormone, so its effect in research models depends on a working pituitary, which makes it useful for separating hypothalamic, pituitary and peripheral signaling. Researchers often compare it with ghrelin-receptor peptides such as Ipamorelin and GHRP-6, which reach the same output through a different receptor; see Ipamorelin vs GHRP-6.

For a longer-lasting GHRH analog with an approved-drug record, see Tesamorelin.

Frequently Asked Questions

What is Sermorelin used for in research?

As a reference GHRH-receptor agonist for studying pulsatile growth hormone release, pituitary function and the IGF-1 axis, including aging-related research.

Is Sermorelin FDA approved?

It was, under the brand name Geref. The manufacturer discontinued it in 2008 for business reasons, and no approved sermorelin product is marketed today.

What is the difference between Sermorelin and Tesamorelin?

Sermorelin is the unmodified first 29 amino acids of GHRH. Tesamorelin is the full 44 amino acids with a trans-3-hexenoyl cap that protects it from breakdown, and it is a currently approved drug (Egrifta).

What is the difference between Sermorelin and CJC-1295?

Both are based on GHRH(1-29). CJC-1295 has four amino acid substitutions for stability, and its DAC version adds a long-acting linker. Sermorelin has no modifications.

What sizes is Sermorelin available in?

5 mg and 10 mg options. Each kit contains 10 vials, verified by HPLC and mass spectrometry. Learn how to read a peptide COA.

How should Sermorelin be stored?

Refrigerated at 2–8 °C (36–46 °F), sealed, dry and away from light. For long-term storage, −20 °C. Sermorelin contains methionine, which oxidizes easily, so keep vials tightly sealed.