Muscle & performanceAnti-aging & longevity
Sermorelin
GRF (1-29) · Geref (former brand)
Sermorelin is the first 29 amino acids of GHRH: the shortest fragment that retains full activity at the receptor. It is the compound CJC-1295 and tesamorelin are both modifications of, which makes it the reference point for that family.
Its regulatory history is unusual and worth stating precisely. Sermorelin held FDA approval as Geref, used diagnostically and in growth hormone deficiency in children. It was withdrawn from the US market in 2008, for commercial reasons, not a safety finding. Compounding pharmacies have continued to supply it under prescription since.
That distinction matters because 'withdrawn' is easily read as 'found to be dangerous'. In this case a product left the market because it stopped making commercial sense, which is a different thing entirely, and this is the only compound on the site where that particular nuance applies.
How it works
Sermorelin binds the GHRH receptor on the pituitary and prompts growth hormone release, exactly as endogenous GHRH does. Because it works through the body's own regulatory loop rather than replacing the hormone, feedback control stays intact. That is the argument made for the whole class.
Its half-life is short, around ten to twenty minutes, because it lacks the enzymatic protection added to CJC-1295 and tesamorelin. That is the trade: the most faithful reproduction of the natural signal, and the least convenient dosing.
Regulatory status — United States
Formerly FDA approved as Geref, withdrawn from the US market in 2008 for commercial rather than safety reasons. Available through compounding pharmacies under prescription. Material sold as a research chemical is not a compounded prescription product.
Last reviewed 12 Aug 2026. Regulatory positions in this category change frequently; we date this line so you can see how current it is.
What it is studied for
Each entry states the evidence behind it. We do not rank indications by effectiveness — for most compounds here, that would be a claim nobody can support.
Growth hormone deficiency in children
Clinical trialIts former approved use.
EvidenceClinical trials supporting the original FDA approval, later withdrawn for commercial reasons.
Diagnostic testing of pituitary function
Clinical trialA well-established clinical use.
EvidenceEstablished clinical application.
Age-related growth hormone decline
Community practiceThe reason it is prescribed by compounding pharmacies.
EvidenceRaises GH and IGF-1 measurably. Outcome trials in healthy older adults are not established.
Identity and clearance
Molecule
- Class
- GHRH (1-29) analogue
- Molecular weight
- 3357.9 Da
- Length
- 29 amino acids
The unmodified active fragment. CJC-1295 and tesamorelin are this backbone with stabilising modifications added.
Pharmacokinetics
Clinical trialTen to twenty minutes, the shortest half-life of anything on this site. It is why dosing is nightly and why the modified analogues exist.
Dose protocols reported in sources
Displayed for reference only. Every row says where it came from, and a trial protocol and a community convention are not the same kind of information. None of this is fed into the calculator, and none of it is a recommendation.
| Goal | Dose | Frequency | Route | Units, 5 mg vial | Source | Start this protocol |
|---|---|---|---|---|---|---|
| Commonly prescribed by compounding pharmacies | 200 mcg – 500 mcg | Once nightly before bed | SubcutaneousTimed to coincide with the largest natural growth hormone pulse during early sleep. | 12–30 u | Community practice | Start this |
Start this copies a row into a protocol of your own, which you can then edit. Where a source gave a dose range or an ambiguous frequency, those fields arrive empty — we will not pick a number on your behalf.
CheckRows marked community practice describe what people commonly do, drawn from public discussion. They are not derived from any trial and are not evidence that a dose is safe or effective.
Cycling
Community practice3 to 6 months on, Variable off.
Longer courses than most of this category, reflecting its use as an ongoing prescription rather than a cycle.
Calculator
Work out what to draw
Pre-filled with a 9 mg vial as a worked example. These are not recommended values — change them to match the vial in front of you.
Draw to 6.67 units on a 1 mL U-100 syringe. That is 0.067 mL, containing 300 mcg of Sermorelin.
Check6.67 units falls between the printed lines on a 1 mL U-100 syringe. Mixing with 1.8 mL of water instead would put this dose at 6 units.
Bioalmanac performs arithmetic on values you enter. It does not recommend doses, schedules or compounds, and nothing here is medical advice. Confirm every calculation against your vial and syringe before drawing, and speak with a licensed healthcare provider.
Open this calculation in the full calculator
Units, concentration, bacteriostatic water — the glossary defines the vocabulary, and a unit is not a fixed volume.
Safety
Reported effects
- Flushing or warmth shortly after injectionClinical trial
Common
- Injection site redness or painClinical trial
Common
- Headache and drowsinessCommunity practice
Occasionally reported
- Water retention or joint discomfortCommunity practice
Occasionally reported
Classic growth hormone effects, more likely at higher doses.
When to stop
- Persistent numbness, tingling or wrist pain, which can indicate fluid-related nerve compression.
- Noticeable swelling of the hands, feet or face.
- Unusual thirst, frequent urination or blurred vision, which can indicate raised blood glucose.
- Any new lump or growth. Investigate rather than watch.
- Any allergic response: rash, hives, facial swelling or difficulty breathing. Seek urgent care.
Interactions and situations that need care
- Active or previous cancerAvoid
Raising growth hormone raises IGF-1, which promotes cell growth and survival. This is contraindicated for growth hormone therapy in active malignancy, and the same reasoning applies to anything that raises GH deliberately.
- Diabetes or impaired glucose toleranceUse caution
Growth hormone opposes insulin and raises blood glucose, working against glycaemic management.
- Pregnancy and breastfeedingAvoid
No reproductive or developmental safety data.
- Competing in a tested sportAvoid
Prohibited at all times under WADA's S2 category.
SportProhibited by the World Anti-Doping Agency under S2: Peptide Hormones, Growth Factors and Related Substances, at all times.
What to expect
- Its established evidence concerns growth hormone deficiency in children and diagnostic pituitary testing, not body composition in healthy adults.
- Its withdrawal from the US market was commercial, not a safety finding. That distinction is frequently lost and cuts in sermorelin's favour rather than against it.
- The very short half-life means nightly dosing, which is less convenient than the modified analogues and is the reason those exist.
- IGF-1 is the measurable thing. A blood test is inexpensive and is the only way to know whether anything is happening.
Storage and handling
- Freeze-dried powder
- Refrigerated at 2–8 °C, protected from light.
- After mixing
- Refrigerated at 2–8 °C. Do not freeze once mixed.
- Long-term, frozen
- Unopened powder is stable at −20 °C or colder.
With other peptides
- Ipamorelinsynergistic
The same two-input logic as CJC-1295 with ipamorelin: a GHRH analogue alongside a ghrelin receptor agonist. Sermorelin's shorter half-life means the combined pulse is briefer.
Checking your vial
Research chemicals carry no manufacturing standard, so what the vial looks like is often the only quality signal available before you use it. More on assessing quality and COAs.
White cake, clear solution
Standard for a peptide of this size.
Collapsed cake or cloudy solution
Indicates heat damage or degradation.
Questions
- Was sermorelin withdrawn because it was unsafe?
- No. Geref was withdrawn from the US market in 2008 for commercial reasons. No safety finding prompted it, and the distinction matters because 'withdrawn' is routinely read as 'found dangerous'.
- How does it compare with CJC-1295?
- CJC-1295 is this molecule with modifications that resist enzymatic breakdown. Sermorelin is the unmodified fragment: the most faithful reproduction of the natural signal, and the shortest-lived.
- Why is it taken at night?
- The largest natural growth hormone pulse occurs during early sleep, and dosing then augments a pulse that is already happening. This is one of the timing conventions in this category with real physiology behind it.
References
Sermorelin: a review of its use in growth hormone assessment and therapy
Review literature, 2010 · Review
Humans, including paediatric populations
Reviews clinical use in growth hormone deficiency and pituitary function testing, and notes the 2008 US market withdrawal as commercial rather than safety-driven.
Commonly reported protocols
Bioalmanac editorial summary of public and compounding-pharmacy sources, 2026 · Not a study
Summarises the nightly dose ranges commonly prescribed and discussed. Carries no evidential weight about outcomes in healthy adults.
Sermorelin compared with
Related compounds
Ipamorelin
A selective growth hormone secretagogue that prompts a short pulse of GH release. Widely used, and supported almost entirely by early pharmacology rather than outcome trials.
GHK-Cu
A naturally occurring copper-binding tripeptide with a long history in topical skincare research. Injected use is not what the research studied.
CJC-1295
A GHRH analogue that raises growth hormone by amplifying the body's own release signal. Sold in two forms whose durations differ by two orders of magnitude.
Tesamorelin
A GHRH analogue approved by the FDA for reducing excess visceral fat in HIV-associated lipodystrophy. The only compound in this category with completed phase 3 trials.
Next
What to do with Sermorelin
- Keep a record of itTurn a dose and a schedule into a protocol, then log what you actually take. Sermorelin is filled in for you.
- See what it costsPer-milligram prices read from vendor sites and confirmed by a person, so vial sizes compare.
- Check a combinationWhat our profiles record about Sermorelin alongside each other compound — including the pairs where nothing is recorded.
Keep this page honest
If something here is wrong, out of date, or missing a source, tell us and we will fix it and say that we did.
This page is educational. It describes what published research reports, not what you should do. Peptides discussed here are largely not approved for human use, and nothing on Bioalmanac is medical advice. No clinician reviews these pages.
Page last updated 12 Aug 2026