Sermorelin
GHRH (1-29)
Sermorelin is a growth-hormone-releasing hormone (GHRH) analog — the peptide that's been the gentle, well-studied entry point to GH-axis support for decades. It nudges your own pituitary to release growth hormone in a natural rhythm, and it even has an FDA-approval history. This guide covers how sermorelin works, what the research shows, dosing references, safety and its current regulatory status.
Sermorelin quick facts
| Reported research dosing | 100mcg-500mcg |
| Route | Subq |
| Cycle length | 3-6 Months |
| Frequency | 1-2x Daily AM/PM · 5 On 2 Off or Daily |
| Half-life | ~10–20 min |
| Forms | Injectable |
| Evidence level | Human (was FDA-approved) |
The entry-level GHRH. Solid, mild, well-tolerated.
How sermorelin works
Sermorelin is a synthetic GHRH (1-29) analog — it's the first 29 amino acids of growth-hormone-releasing hormone, which research showed is the portion needed for full activity at the GHRH receptor. It binds those receptors on the pituitary and triggers a pulse of your own growth hormone. Its very short half-life (about 11–12 minutes) is actually a feature: it prompts a pulse and clears out fast, leaving your body's natural GH rhythm intact rather than overriding it.
What the research & clinical use show
Sermorelin has a real clinical history — it was FDA-approved in 1997 (as Geref) to treat childhood growth-hormone deficiency. Today it's discussed in adult wellness and longevity medicine for goals like energy, sleep quality, body composition and recovery. The honest caveat: strong evidence for clinical benefit in otherwise-healthy aging adults is limited, even though the mechanism is plausible and it's generally considered a gentle option.
Sermorelin dosing (research reference)
Most protocols in the literature reference 200–300 mcg once nightly, subcutaneously, about 30–60 minutes before bed on an empty stomach — timed to ride along with the body's largest natural GH pulse during early sleep. It's reconstituted with bacteriostatic water; the calculator above converts a research amount into syringe units. This summarizes existing references for education only, not dosing advice.
Safety & side effects
Sermorelin is generally considered one of the gentler GH-axis peptides, with injection-site reactions and flushing among the more common minor effects. The important caution applies to the whole class: it works by raising GH and IGF-1, and elevated IGF-1 has been associated with increased risk of certain cancers and can promote the growth of existing tumors. That's a real reason it warrants professional oversight rather than casual use.
Sermorelin vs the other GH options
Sermorelin (GHRH 1-29) is the classic gentle GHRH. Tesamorelin is a stronger, FDA-approved GHRH analog aimed at visceral fat. The CJC-1295 + Ipamorelin stack pairs a longer-acting GHRH with a GHRP for a bigger pulse, and MK-677 is the oral option. Sermorelin's appeal is its simplicity, short physiologic pulse, and track record.
Legal & regulatory status
Sermorelin is not currently a marketed FDA-approved drug (the original approval was discontinued in 2008 for commercial reasons), but as of 2026 it sits in FDA 503A Category 1, meaning licensed compounding pharmacies can legally prepare it. GH secretagogues are also banned in competitive sport under WADA. Follow the laws that apply to you.
Where to get Sermorelin
Buy Sermorelin at Flawless Compounds →Sermorelin reconstitution calculator
Research reconstitution calculator
Bacteriostatic water is the diluent — sterile water with 0.9% benzyl alcohol, which is what lets a vial be drawn from more than once. It does not come with the vial, and unlike the compound it is bought again every time.
Need bacteriostatic water? Get it at AminoWell USA (my company) → Code CAMERON.
The evidence for Sermorelin
Graded by what exists behind each claim.
✅ Clinically validated
- Was FDA-approved (as Geref) for pediatric growth-hormone deficiency and used as a diagnostic agent for GH reserve, so the human pharmacology is properly characterized. It was withdrawn commercially rather than for safety — a business decision, which is a distinction worth knowing.
📊 Correlative data
- Two decades of use in anti-ageing and hormone clinics, almost all of it unpublished. The consistent clinical observation is better sleep quality within weeks and body-composition change over months, in that order.
- Beyond that the record is self-reported: community dosing logs are real information about tolerability and almost none about efficacy.
🧪 Theoretical / extrapolated
- A GHRH fragment (1–29), so the same pituitary-level mechanism as tesamorelin with a much shorter half-life. The short action predicts what users report: a sharp pulse that suits bedtime dosing, and tolerance if you dose it too often to let the axis reset.
What community dosing logs are worth →
How to read these tiers: they say how much human evidence exists, not how well something works — and ✗ flags harm, never a disappointing trial. How the evidence tiers work →
What Sermorelin actually does
Sermorelin is the first 29 residues of human growth hormone-releasing hormone, with the C-terminus amidated. Native GHRH is 44 amino acids; residues 1–29 carry essentially all the biological activity, and the remaining 15 contribute little. The amide cap at the C-terminus is not cosmetic — it removes the terminal carboxylate, which is both a negative charge and a carboxypeptidase substrate.
The receptor is a class B G-protein-coupled receptor and the signaling is textbook. GHRH binds the GHRH receptor on pituitary somatotropes, which couples to Gs, raises cyclic AMP, activates protein kinase A, and drives both immediate release of stored growth hormone and, through CREB and the transcription factor POU1F1, transcription of new GH. The consequence that matters is that it cannot work without functioning somatotropes. An empty pituitary produces nothing, which is exactly why the compound is useful as a diagnostic agent and why it is a poor choice in someone whose pituitary is the problem.
The half-life has a named cause, and knowing it explains every other GHRH analog on this site. Position 1 is tyrosine and position 2 is alanine, and dipeptidyl peptidase-4 cleaves exactly that Tyr-Ala pair, producing GHRH(3-29), which does not activate the receptor. DPP-4 is abundant on endothelium and in plasma, so the peptide is being destroyed from the moment it is absorbed. That single enzyme is why the card says 10–20 minutes, and it is why every longer-acting GHRH analog — modified GRF 1-29, CJC-1295 — substitutes position 2 with a D-amino acid. Sermorelin is the unmodified parent, and its brevity is a design absence rather than a design choice.
The brake nobody mentions: somatostatin. GH release is controlled by two hypothalamic peptides in opposition — GHRH pushing and somatostatin holding. Somatostatin tone rises after meals and varies across the day, and when it is high the somatotrope will not respond well to GHRH however much you give. This is the actual pharmacological reason for fasted and bedtime dosing, and it is why the same dose produces different results at different times — a fact usually presented as folklore.
Cell, rodent, human — and where it stops
Step one, in humans, and this is unusual for the Vault: sermorelin was a licensed drug. Prakash 1999 reviews its use in children with idiopathic growth hormone deficiency at 30 mcg/kg subcutaneously daily at bedtime, for up to 36 months. Significant increases in height velocity were sustained through 12 months of treatment, with catch-up growth in the majority. Adverse events were transient facial flushing and injection site pain.
Read the dose against the dose on this page's card. The pediatric dose is 30 mcg/kg — roughly 900 mcg in a 30 kg child, and well over 2 mg at adult body weight. The card lists 100–500 mcg. The community dose is a fraction of the only dose ever shown to change a clinical endpoint, and the bedtime timing that people treat as a lifestyle preference is the timing the licensed protocol used, for the somatostatin reason above.
Step two, as a diagnostic agent. GHRH-based stimulation testing was a standard way to probe pituitary GH reserve Casanueva 1996, and it works because the response is a direct readout of somatotrope capacity. The field has since moved to macimorelin, an oral ghrelin-receptor agonist validated against the reference standard for adult GH deficiency Garcia 2013 — which is worth knowing because it means the diagnostic literature that would have generated modern adult sermorelin data went elsewhere.
Step three, in adults using it for body composition: no controlled trial exists. The nearest human evidence is for growth hormone secretagogues as a class in hypogonadal men Sinha 2020, and the class is not the compound. There is no randomized trial of sermorelin in healthy adults with a body composition, sleep or recovery endpoint.
The obstacles, named one at a time. (1) The efficacy data is pediatric, in children whose GH axis is deficient, at a dose several times what adults use Prakash 1999. (2) The GH axis declines with age partly through rising somatostatin tone and falling somatotrope responsiveness, so an older adult is the person in whom a GHRH analog should work least well — the opposite of how it is marketed. (3) A 10–20 minute half-life against a physiological GH pulse pattern of a few pulses a day means the timing of the injection may matter more than the dose, and nobody has optimized it. (4) The product was withdrawn commercially rather than for safety, which is a genuine distinction and also means no sponsor has generated data on it for two decades.
What would have to be true, and how you would know it was not
Three predictions, and the first is the one measurement that separates this compound working from this compound being expensive.
1. IGF-1 is the integrated readout, and a single growth hormone level is not. GH is released in pulses and a random growth hormone draw can be near zero in someone with a perfectly normal axis; IGF-1 is produced by the liver in response to cumulative GH exposure and is stable across the day, which makes it the correct instrument. Draw IGF-1 at baseline and at 8–12 weeks, from the same laboratory both times, because inter-assay differences between labs are larger than the effect you are looking for. A flat IGF-1 after three months means the dose or the timing is not producing enough GH exposure to matter, and that is a clean falsification of the protocol rather than of the molecule.
2. The prediction that cuts against the product: fasting insulin should be watched, because GH is a counter-regulatory hormone. Growth hormone opposes insulin action — it promotes lipolysis and reduces peripheral glucose uptake — and that is not a side effect, it is what GH does. If sermorelin is genuinely raising GH exposure, the mechanistic prediction is a small rise in fasting insulin and possibly in HbA1c. Finding no change in either while claiming a GH effect is internally inconsistent, and finding a large change is a reason to reduce the dose.
3. Timing is a testable variable and almost nobody tests it. Somatostatin tone rises after eating, so the same dose given fasted and given after a meal should produce different IGF-1 trajectories over weeks. Run 8 weeks of bedtime fasted dosing, measure IGF-1, then 8 weeks of a different schedule at the same dose and measure again. That is a within-person crossover, it costs two blood draws, and it would tell an individual more than any forum consensus.
What nobody has tested yet
Four experiments nobody has run on a compound that was once an approved drug.
Nobody has established an adult dose-response. The only dose with an efficacy endpoint behind it is 30 mcg/kg in children Prakash 1999. What 100, 300 and 500 mcg do to IGF-1 in a healthy 40-year-old over 12 weeks has never been measured, and it is three arms and two blood draws each.
Nobody has tested whether adding a DPP-4 inhibitor works. The half-life is set by DPP-4 cleaving Tyr1-Ala2. DPP-4 inhibitors are licensed oral drugs taken by millions of people for diabetes. The mechanistic prediction — that a DPP-4 inhibitor should substantially extend sermorelin's action — is obvious, specific, testable, and completely unstudied in either direction. It is also, incidentally, the most interesting unasked question on this page.
Nobody has compared sermorelin against modified GRF 1-29 in a person. The two differ by the substitutions that block that same enzyme. A head-to-head with IGF-1 as the endpoint would tell buyers whether the more expensive analog is worth it, and the comparison has never been published.
Nobody has measured whether older adults respond at all. The mechanism predicts a blunted response with age through rising somatostatin tone and reduced somatotrope reserve. If that is right, the population buying this is the population it works least well in, and an age-stratified IGF-1 response study would establish it one way or the other.
Sermorelin — its own safety story, not its class's
Sermorelin has a better-defined safety position than almost anything else in this section, and the reasons are specific.
It works through your own pituitary, and that is a real safety feature rather than marketing. Exogenous growth hormone bypasses every control the body has. A GHRH analog acts upstream, and the negative feedback loops — somatostatin release, IGF-1 feedback at the pituitary and hypothalamus — remain intact. The system retains a ceiling, which is why supraphysiological IGF-1 is much harder to produce this way than with injected GH.
The reported adverse effects are minor and mechanistically explicable. Transient facial flushing and injection-site pain Prakash 1999: flushing is consistent with mast-cell histamine release, which several basic peptides cause, and it is why the sensation is immediate and short.
The GH-related cautions apply to whatever GH you release, not to the peptide. Carpal tunnel symptoms, joint aches and fluid retention are dose-related consequences of raised GH and appear when the axis is pushed hard. They are the practical ceiling on dosing and they resolve on reduction.
The withdrawal was commercial, and the distinction matters both ways. Geref was discontinued as a business decision, not for a safety finding — which is genuinely reassuring about the 36 months of pediatric exposure behind it Prakash 1999. It also means no pharmaceutical-grade product exists, so everything in circulation is compounded or research-grade, and the safety record of the licensed drug does not automatically transfer to an unlicensed vial.
Who should not treat this as benign. Anyone with an active malignancy, because GH and IGF-1 are growth signals; and anyone with a known pituitary lesion, because stimulating somatotropes is not obviously neutral in that setting. Neither has been studied with this compound, and both are reasoning from the axis rather than from a trial.
Sources read for this page
- Prakash A, Goa KL. Sermorelin: a review of its use in the diagnosis and treatment of children with idiopathic growth hormone deficiency. BioDrugs 1999 · PMID 18031173
- Garcia JM, et al. Macimorelin (AEZS-130)-stimulated growth hormone (GH) test: validation of a novel oral stimulation test for the diagnosis of adult GH deficiency. Journal of Clinical Endocrinology and Metabolism 2013 · PMID 23559086
- Casanueva FF, Dieguez C. Role of the new growth hormone-releasing secretagogues in the diagnosis of some hypothalamopituitary pathologies. Metabolism 1996 · PMID 8769405
- Sinha DK, et al. Beyond the androgen receptor: the role of growth hormone secretagogues in the modern management of body composition in hypogonadal males. Translational Andrology and Urology 2020 · PMID 32257855
Sermorelin — safety, predicted from mechanism
Predicted from mechanism, not from a human safety trial. How that reasoning works →
What the mechanism predicts
Derived from the molecule, not a trial.
- Everything here follows from one fact: these raise GH and therefore IGF-1. The predicted problems are the known consequences of elevated GH/IGF-1, drawn from acromegaly and clinical GH therapy where it HAS been studied — insulin resistance and rising fasting glucose, fluid retention (puffy hands and face, and the ring that stops fitting), carpal tunnel symptoms from that same fluid pressing on the median nerve, and joint aches.
- The proliferation question is the serious one. IGF-1 is a growth signal, and growth signals do not distinguish between tissue you want to grow and tissue you do not. There is no evidence these compounds cause cancer. There is also a clear mechanistic reason not to run them with an active or recent malignancy, and that reasoning does not require a trial to be sound.
What has actually been reported
- Injection-site reactions, transient flushing, tingling and head-rush on dosing — most commonly with the GHRPs, which also release cortisol and prolactin at higher doses.
- Increased hunger is near-universal with the ghrelin-mimetic ones (GHRP-6, MK-677, Hexarelin). That is the mechanism working, not a side effect — the same receptor drives GH release and appetite.
How to reduce the risk
Same mechanism as the prediction.
- Draw an IGF-1 baseline BEFORE you start. Once you are on, that number is the drug and you have permanently lost the comparison. This is the single highest-value thing on this list and it costs one blood draw.
- Watch fasting glucose and HbA1c, not the scale. Insulin resistance is the most likely thing to move and the one you cannot feel. Re-test at 8–12 weeks. If fasting glucose is climbing, that is your signal to cut the dose or come off — long before anything shows up symptomatically.
- Dose at night, on an empty stomach. GH release is pulsatile and largest during early sleep; food, and carbohydrate in particular, blunts the pulse through insulin. This is not a ritual — it is the same mechanism working with you rather than against you.
- Don't run a secretagogue through a high-carbohydrate surplus. The predicted problem is insulin resistance; adding a large carb load is pushing the same lever from the other end.
- Cycle rather than run continuously. Most of the predicted problems — fluid retention, carpal tunnel, glucose drift — are dose-and-duration dependent and reverse on cessation. Time off is the cheapest safety intervention available.
- If fluid retention is the issue, it usually resolves on a dose reduction long before it needs anything else. Reach for the dose before you reach for a diuretic.
What it does to your bloodwork
A fact about the assay.
- IGF-1 drawn on-cycle is not your baseline — it is the drug working, and it will read high. If you want a real baseline, draw before starting or after a proper washout.
- Watch fasting glucose and HbA1c, because insulin resistance is the most likely thing to move and the one you will not feel.
- GHRP-6 and Hexarelin can raise prolactin and cortisol; if you are chasing an unexplained prolactin result, this is a candidate.
What it overlaps with
- Stacking two secretagogues that work by the same route is redundancy, not synergy. A GHRH analog (CJC-1295, Sermorelin, Tesamorelin) plus a ghrelin mimetic (Ipamorelin, GHRP-2, GHRP-6) is the deliberate pairing — two different levers on the same axis. Two GHRH analogs together is paying twice for one lever.
Don't run this if
- Active or recent malignancy — the IGF-1 reasoning above.
- Diabetes or poor glycemic control, unless you are monitoring fasting glucose and HbA1c and know what you are looking at.
- Untreated diabetic retinopathy.
The honest unknown
- Nobody has run long-term studies of intermittent secretagogue use in healthy adults. The specific unmeasured thing is what years of repeatedly pushing IGF-1 above your natural set point does — not whether a single cycle is tolerable, which it evidently is.
Not medical advice. If you take prescription medication or have a diagnosed condition, check this with a pharmacist or doctor.
Fasted — and pre-bed is the best of the windows
Food is the problem here, and specifically carbohydrate and fat. Both trigger somatostatin release, and somatostatin is the brake on growth hormone — eating before the injection pharmacologically cancels it. Two clear hours either side.
Pre-bed is the strongest window because the largest natural GH pulse happens in the first hours of deep sleep, so you are stacking with it rather than asking the pituitary for something it is not primed for. Fasted pre-training is the second-best, for the same reason in a different rhythm.
From half-life and route, not a dosing trial.
Sermorelin — interference & stacking
Predicted from mechanism, not from an interaction study. How mechanism-predicted claims are made →
What Sermorelin moves on your bloodwork
Expected direction, not a measured one.
- IGF-1 (Insulin-like Growth Factor 1) — ↑ expected to rise
This is the point. IGF-1 rising is the compound doing its job — it is the stable downstream readout of a GH pulse.
What to do: Test it before you start and again at 6–8 weeks. It is the only number that tells you whether the product was real and the dose was enough. - Growth Hormone, Serum — ✕ unreliable here
A random GH level is close to meaningless here. GH is secreted in pulses during deep sleep and sits undetectable between them, so a daytime draw catches a trough almost every time — including when the compound is working perfectly.
What to do: Do not use GH to judge a secretagogue. Read IGF-1 instead. - Fasting Insulin — ↑ expected to rise
GH is a counter-regulatory hormone: it opposes insulin. Fasting insulin and glucose drifting up is the predicted trade-off, not a surprise.
What to do: Check fasting insulin and HbA1c at baseline and again at 8–12 weeks. This is the marker that decides whether you keep running it. - HbA1c (Hemoglobin A1c) — ↑ expected to rise
Same mechanism, longer window — a slow drift rather than a jump.
What to do: Pair it with fasting insulin; either alone can mislead. - Free T4 (Thyroxine) — ↓ expected to fall
GH accelerates the peripheral conversion of T4 to T3, so free T4 can fall while free T3 holds or rises. Read alone it looks like new hypothyroidism, and it usually isn't.
What to do: Run a full thyroid panel rather than TSH alone before concluding anything.
Everything above follows from one fact: these raise GH and therefore IGF-1. Nothing here needs a trial of the specific molecule.
Everything on this page, in an order
This one is free and stays free. What Skool adds is the rest of the shelf — 278 compounds and 371 supplements with the protocol, the stack order and the bloodwork to run beside it.
Join Skool — $10/mo →Bloodwork to run alongside Sermorelin
Baseline first, then again at 8–12 weeks.
| Marker | What it’s watching for |
|---|---|
| IGF-1 (Insulin-like Growth Factor 1) | The dosing target — feel is not a measurement |
| Fasting Insulin | The insulin trade that comes with every secretagogue |
| HbA1c (Hemoglobin A1c) | Three-month confirmation |
| Comprehensive Metabolic Panel (CMP) | Fasting glucose and organ baseline |
The “Running GH Peptides or MK-677” panel covers these in one order — 9 markers, $132.30 with the discount applied.
Check results you already have → · All 103 markers A–Z
Sermorelin — frequently asked questions
What is sermorelin?
Sermorelin is a synthetic GHRH (1-29) analog that prompts your pituitary to release your own growth hormone in a natural pulse. It has an FDA-approval history and is considered a gentle GH-axis option.
How does sermorelin work?
It binds GHRH receptors on the pituitary to trigger a GH pulse, then clears fast (~11–12 minute half-life), preserving your natural GH rhythm rather than overriding it like injected HGH.
How is sermorelin dosed?
The literature commonly references 200–300 mcg once nightly, subcutaneously, ~30–60 minutes before bed on an empty stomach to align with the natural nighttime GH pulse. Reconstituted with bacteriostatic water (see calculator). This is educational, not dosing advice.
Is sermorelin FDA-approved?
Not currently as a marketed drug — the original approval (Geref) was discontinued in 2008. But it sits in FDA 503A Category 1, so compounding pharmacies can legally prepare it.
What are the side effects of sermorelin?
Usually mild — injection-site reactions and flushing. The class-wide caution is that raising GH/IGF-1 has been linked to certain cancer risks and can promote existing tumors, so it warrants professional oversight.
Sermorelin vs CJC-1295 / Ipamorelin?
Sermorelin is a simple, gentle, short-acting GHRH. CJC-1295 + Ipamorelin pairs a longer-acting GHRH with a GHRP for a larger, synergistic pulse. Different intensity, same GH axis.
References & further reading
- Sermorelin: how it works, safety and access (Testing.com)
- Sermorelin: complete guide to the GHRH (1-29) analog
Sermorelin inside a finished plan
One arm of 1 Protocol Blueprint, free to read in full.
What Sermorelin is used for
Sermorelin appears under 3 goals in the goal router.
Related GH & Growth compounds
Where this goes next
Sermorelin is the depth arm of this plan. The page above is the free breakdown of one compound; the plan it belongs to — the dosing, the order to correct things in, the week-by-week schedule and what to retest — is a lesson inside Skool.