Sermorelin: research protocol, dosing & reconstitution
Also known as: GHRH (1-29), Geref
Quick answer
What is Sermorelin?
Sermorelin is the first 29 amino acids of the body's own growth-hormone-releasing hormone — the shortest piece that still works. It was an approved medicine for diagnosing and treating growth hormone deficiency in children, which gives it a clinical history most research peptides lack.
What Sermorelin is
Natural GHRH is 44 amino acidsAmino acidThe chemical building block of peptides and proteins. Peptides are short chains of amino acids linked together by peptide bonds.See glossary → long, but only the first 29 are needed for full activity. Sermorelin is that fragment, GHRH(1-29), made synthetically.
It was marketed as Geref and approved for paediatric growth hormoneGH (growth hormone)A hormone produced by the pituitary gland involved in growth, metabolism, and tissue repair. Several research peptides are studied for their ability to stimulate GH release.See glossary → deficiency before being withdrawn commercially — a business decision rather than a safety one. That history means sermorelin has published clinical dosing behind it, unlike most compounds in this category.
Research vialsVialThe small sealed glass container peptides are supplied in, topped with a rubber septum that a syringe needle can pass through.See glossary → are typically 2 mg, 5 mg or 10 mg of lyophilizedLyophilizedFreeze-dried. Peptides are shipped as a lyophilized powder ('puck') because the dry form is far more stable than a solution. It must be reconstituted before use in research.See glossary → powder.
Mechanism of action
Sermorelin binds the GHRH receptorReceptorA protein on or inside a cell that binds specific signaling molecules and triggers a response. Most peptides work by binding particular receptors.See glossary → on the pituitary and triggers growth hormone release, which in turn raises IGF-1IGF-1 (insulin-like growth factor 1)A hormone produced mainly by the liver in response to growth hormone. IGF-1 levels are a common downstream marker in GH-axis research.See glossary →. Because it works through the body's own signalling rather than supplying external GH, the pituitary's feedback controls stay intact — a 2006 review frames this as the central argument for GHRH analogues over exogenous growth hormone in adult GH insufficiency [1].
Its clinical pedigree is in paediatrics. A review of its use in diagnosing and treating idiopathic growth hormone deficiency in children documents the dosing and response data from that program [2].
What researchers study Sermorelin for
- Growth hormone axis stimulation and IGF-1 response
- Diagnostic testing of pituitary GH reserve
- Body-composition and sleep-quality research contexts
- Comparison against exogenous GH administration
What dose of Sermorelin do researchers use?
Research literature commonly references doses of 100–300 mcg nightly (literature-referenced). This is not a recommendation — the table below summarizes protocols as they appear in published literature and trial designs.
| Context | Dose | Frequency | Duration |
|---|---|---|---|
| Research literature reference | 100–300 mcg | Nightly, empty stomach | 8–12 week cycles referenced |
| Blend with Ipamorelin | Sermorelin plus a ghrelin-receptor agonist | Nightly before bed | 8–12 week cycles referenced |
← Swipe to see the full table
Half-life and dosing timing
Half-life: ~11–12 minutes (very short). Route referenced in research: Subcutaneous. The half-lifeHalf-lifeHow long it takes for half of a compound to be eliminated from the body. Half-life determines how often researchers dose a compound in protocols.See glossary → is about 11–12 minutes — very short even by GH-axis standards. That is the point: a brief signal produces a discrete GH pulse rather than a sustained elevation. Protocols reference dosing before bed on an empty stomach, to land on the body's own largest nightly GH surge.
Titration: start low, go slow
Literature-referenced protocols start at the low end (around 100 mcgMicrogram (mcg / µg)One millionth of a gram, or one thousandth of a milligram. Most peptide research doses are measured in micrograms.See glossary → nightly) and increase only after several days, watching for flushing or a head-rush — the same start-low pattern used across the GH-axis class.
Skip the Sermorelin math
Enter vial size, water volume, and target dose — the free calculator returns concentration, injection volume, and exact U-100 syringe units.
How is Sermorelin reconstituted?
| Vial size | BAC water | Concentration | Worked example |
|---|---|---|---|
| 5 mg | 2.5 mL | 2,000 mcg/mL | 200 mcg = 0.1 mL = 10 units on a U-100 syringe |
| 2 mg | 1 mL | 2,000 mcg/mL | 300 mcg = 0.15 mL = 15 units on a U-100 syringe |
Add 2.5 mL of bacteriostatic waterBAC water (bacteriostatic water)Sterile water containing 0.9% benzyl alcohol, which suppresses bacterial growth. It is the standard diluent used to reconstitute lyophilized peptides for multi-dose research vials.See glossary → to a 5 mg vial: 5 ÷ 2.5 = 2 mg/mL, or 2,000 mcg/mL. A 200 mcg dose is 200 ÷ 2,000 = 0.1 mL — 10 units on a U-100 syringeU-100 syringeAn insulin syringe calibrated so that 100 units equal 1 mL. The standard syringe referenced in peptide research; each unit equals 0.01 mL.See glossary →.
New to the process? Read the full step-by-step reconstitution guide.
How long does reconstituted Sermorelin last?
Lyophilized: refrigerate. ReconstitutedReconstitutionThe process of mixing a freeze-dried (lyophilized) peptide powder with bacteriostatic water to create a solution of known concentration.See glossary →: refrigerate at 2–8°C and use within about 28 days — the same shorter window that applies across GH-axis peptides, rather than the ~60 days seen with BPC-157 or TB-500.
What is Sermorelin stacked with in research?
Paired with Ipamorelin on the same logic as CJC-1295: sermorelin amplifies the GHRH signal while Ipamorelin fires the separate ghrelin receptor, and research references the combined pulse as larger than either alone.
Side effects observed in research
Injection-site redness or pain, flushing, and headache are the commonly reported effects, consistent with the paediatric clinical program. As with all GH-axis stimulation, prolonged use can affect glucose regulation.
- Injection-site redness or pain
- Flushing
- Headache
Frequently asked questions
How is Sermorelin different from CJC-1295?
Both are GHRH analogues. Sermorelin is the natural GHRH(1-29) fragment with a very short half-life; CJC-1295 is modified to resist breakdown and act longer. Sermorelin also carries a clinical approval history that CJC-1295 does not.
What dose of Sermorelin do research protocols reference?
Commonly 100–300 mcg nightly on an empty stomach. This describes research protocol convention; the approved paediatric dosing was weight-based and set for a different purpose.
Why is Sermorelin dosed at night?
The body's largest natural GH pulse occurs in early deep sleep, and food raises blood glucose and fatty acids which blunt GH release. Dosing before bed on an empty stomach works with both facts.
Is Sermorelin still an approved drug?
It was approved as Geref for paediatric growth hormone deficiency but was withdrawn from the market commercially. Research-vendor sermorelin is a Research Use Only chemical.
Related research peptides
CJC-1295
A growth-hormone-releasing hormone analog studied for stimulating GH release; often blended with Ipamorelin.
Growth Hormone SecretagogueIpamorelin
A selective ghrelin-receptor agonist / GH secretagogue studied for stimulating GH with minimal effect on cortisol or prolactin.
Growth Hormone SecretagogueTesamorelin
A GHRH analog studied and approved for reduction of visceral adipose tissue; researched for body composition.
Browse all Growth Hormone Secretagogue peptides or start with the beginner’s guide to research peptides.