Sermorelin vs Ipamorelin: Evidence, Doses and Differences

The Short Answer

No trial ranks them, because none has compared them. What the sources here establish is that they are different in kind, not in degree. Sermorelin is a growth hormone releasing hormone analogue, the fragment GRF 1-29, in the same family as tesamorelin and CJC-1295 (PMID 37806509). Ipamorelin is a growth hormone secretagogue, a pentapeptide that releases growth hormone through a GHRP like receptor and not through the GHRH receptor at all (PMID 9849822).

The cleanest real difference is regulatory, not a performance number. Sermorelin was an FDA approved active ingredient, sold as GEREF, approved in 1990 and 1997, then discontinued by its sponsor in 2008 and withdrawn by FDA in 2009, a withdrawal FDA later said was not for reasons of safety or effectiveness (Federal Register 78 FR 14095). Ipamorelin was never approved, and in 2023 FDA placed ipamorelin acetate in compounding category 2, its list of bulk substances that may present significant safety risks (FDA).

The human trial evidence for both is thin and sits off to the side of what people actually search for. Ipamorelin has two registered Phase 2 trials, both in post-operative gut recovery, both with no results posted. Sermorelin's registered human use retrieved here is a growth hormone stimulation test, which is its old diagnostic job. Neither has a body composition or anti-aging trial in this research. Read that as what was retrieved, not as proof none exist.

What Each One Actually Is

Sermorelin is a 29 residue fragment of growth hormone releasing hormone, denoted GRF 1-29. Anti-doping chemistry work lists it among the growth hormone releasing hormone synthetic analogs alongside tesamorelin and CJC-1295 (PMID 37806509, PMID 34665524). Mechanistically it is a GHRH analogue: it tells the pituitary to release growth hormone the way the body's own GHRH does, by mimicking that endogenous hormone.

Ipamorelin is a pentapeptide, sequence Aib-His-D-2-Nal-D-Phe-Lys-NH2, derived by removing the central Ala-Trp dipeptide of GHRP-1 (PMID 9849822). It releases growth hormone through a GHRP like receptor, and profiling against GHRH and GHRP antagonists shows it does not act at the GHRH receptor (PMID 9849822). A separate rat study classes ipamorelin among ghrelin mimetics, whose anti-nociceptive effects were blocked by a ghrelin receptor antagonist (PMID 32801950). Its original characterization called it "the first GHRP-receptor agonist with a selectivity for GH release similar to that displayed by GHRH" (PMID 9849822).

A 2026 review puts the split in a single sentence, sorting "growth hormone secretagogues (e.g., Ipamorelin)" apart from "growth hormone-releasing hormone analogues (e.g., CJC-1295, Sermorelin)" (PMID 41880199). Both end at more growth hormone, but they get there through two different doors. That is the difference the marketing usually blurs.

Both are peptides. For the residue-level detail, receptor pharmacology and the fuller literature on each, see the sermorelin profile and the ipamorelin profile.

Regulatory and Doping Status

This is where the two compounds genuinely diverge, and it is documented rather than inferred. Sermorelin acetate was an FDA approved active ingredient under two new drug applications. NDA 19-863 covered GEREF at a strength of 0.05 mg base per ampoule, approved December 28, 1990, and was indicated for evaluating the ability of the pituitary to secrete growth hormone, a diagnostic test. NDA 20-443 covered GEREF at 0.5 and 1.0 mg base per vial, approved September 26, 1997, and was indicated for idiopathic growth hormone deficiency in children with growth failure (approved product strengths, not a dosing schedule, Federal Register 78 FR 14095; Drugs@FDA).

EMD Serono discontinued both products in 2008 and FDA withdrew approval of both NDAs effective June 18, 2009. In a 2013 notice FDA determined that both GEREF products "were not withdrawn from sale for reasons of safety or effectiveness" (Federal Register 78 FR 14095). As of September 2026 there is no current FDA labeled sermorelin product: openFDA returns no label and DailyMed lists none. One honest limit for this guide: the GEREF prescribing label itself could not be retrieved, so the approved product strengths and indications above are sourced, but no daily treatment dose from that label is. Those strengths are label figures from a withdrawn approval, not a schedule to follow.

Ipamorelin has never been an FDA approved drug substance. Four separate openFDA queries returned no record while the same endpoints returned sermorelin acetate in the same session (Drugs@FDA, openFDA). In September 2023 FDA placed ipamorelin acetate in category 2 of the bulk drug substances nominated under section 503B, the tier for substances where FDA "has identified significant safety risks relating to the use of these substances in compounding pending further evaluation" (FDA). Sermorelin does not appear on that same category 2 page as of September 2026, and neither compound appears on the section 503A bulks list page that was checked. That absence is specific to those two pages; it does not mean sermorelin is cleared for compounding anywhere.

On doping, anti-doping laboratory papers state that growth hormone releasing hormone and its synthetic analogs are prohibited by the World Anti-Doping Agency, and they name sermorelin, as GRF 1-29, among those analogs (PMID 34665524, PMID 37806509). For ipamorelin, this research did not retrieve a primary WADA source that names it. It shows up in black market product analysis as a growth hormone releasing peptide, including the identification of a black market analogue, Gly-Ipamorelin (PMID 29864719). Because nothing retrieved here establishes ipamorelin's listing, this guide does not assert it, in either direction.

Human Evidence, Side by Side

The largest registered human trial of ipamorelin is NCT01280344: a Phase 2, randomized, quadruple masked, placebo controlled dose finding study run by Helsinn Therapeutics, April 2011 to May 2014, with an actual enrollment of 320 patients recovering from small or large bowel resection. Its arms gave ipamorelin intravenously at 0.03 mg/kg twice daily, 0.06 mg/kg twice daily, and 0.06 mg/kg three times daily, against matching placebo (trial doses, not a recommendation, NCT01280344). The measured outcome was recovery of gastrointestinal function, up to 10 days. No results section is posted, so whether ipamorelin met or missed that endpoint is unknown from the registry.

An earlier trial, NCT00672074, was Phase 2 for post-operative ileus, same sponsor, 117 patients, also intravenous, with the same recovery of gastrointestinal function endpoint. The dose is not stated in that registry record, and again no results were posted. Both registered ipamorelin trials are Phase 2 and both are in post-operative gut recovery; the ClinicalTrials.gov search returned no Phase 3 trial and nothing in body composition, anti-aging, muscle gain or fat loss.

Review articles describe that evidence base bluntly. One 2026 scoping review of six peptides used in sports medicine, ipamorelin among them, found that human clinical studies were "limited to a handful of investigations, most lacking robust controls or rigorous study designs," with "significant heterogeneity ... in dosing and route of administration" (PMID 42578445). Another states that "information regarding the indications, dosing, frequency, and duration of treatment remains unknown" (PMID 41476424), and a third notes "there is a current lack of clinical trials" (PMID 41490200).

For sermorelin, the registered human use retrieved here is diagnostic. NCT00324064, run at Children's Mercy Hospital from 2007 to 2009 with an estimated 90 participants, used sermorelin, labeled as GHRH (Geref), as a single 1 mcg/kg intravenous push followed by an arginine infusion, measuring the serum growth hormone response (trial dose, not a recommendation, NCT00324064). That is the stimulation test, and it matches the 0.05 mg ampoule indication above rather than any body composition use.

One review of growth hormone secretagogues in hypogonadal men, which discusses both compounds, states they "can significantly improve body composition" while cautioning in the same breath that "a paucity of data examining the clinical effects of these compounds currently limits our understanding" (PMID 32257855). Those two clauses belong together; the second is what keeps the first honest. No body composition, sleep, IGF-1 or anti-aging trial for either compound was retrieved in this research, which is a limit of one search, not a finding that none exist.

Side by Side Comparison

Read down the table and the pattern is not that one compound wins. It is that they answer different questions. Sermorelin carries a real, if withdrawn, approval history and a documented diagnostic use. Ipamorelin carries more mechanistic and selectivity data, most of it from animals, plus an explicit FDA safety flag and two human trials that never reported out.

The rows that say "none retrieved" or "no figure" are doing as much work as the rows with numbers. They mark where the popular claims about these peptides, the half lives, the body composition results, the direct comparison, run past what any source here actually supports.

What the Animal Data Shows

Most of the pharmacology that gets cited for ipamorelin is animal or in vitro. In its original characterization, ipamorelin released growth hormone from rat pituitary cells with potency similar to GHRP-6, and in anaesthetised rats it acted with an ED50 of about 80 nmol/kg, while in conscious swine the ED50 was about 2.3 nmol/kg (animal study, rats and swine, route not stated in the abstract, PMID 9849822). These are potency measures in animals, not human doses.

The single most repeated selling point for ipamorelin is its selectivity, and it needs its species label kept on. In swine, GHRP-6 and GHRP-2 raised plasma ACTH and cortisol, while ipamorelin "did not release ACTH or cortisol in levels significantly different from those observed following GHRH stimulation," an effect that held even at doses more than 200 fold above the ED50 for growth hormone release (animal study, swine, route not stated in the abstract, PMID 9849822). In the same swine work it also did not affect FSH, LH, prolactin or TSH. This is a pig finding. No source retrieved here extends that cortisol selectivity to humans, so a page that presents it as a human advantage is overreaching.

Other animal work on ipamorelin: it attenuated colonic hypersensitivity in a rat nociception model, given intravenously, with the dose not stated in the abstract (animal study, rats, intravenous, PMID 32801950); and combined with CJC-1295 it improved maximum tetanic tension in mice with glucocorticoid induced muscle loss, findings the authors explicitly call "limited to animal studies" (animal study, mice, route not stated in the abstract, PMID 41476424). One scoping review notes that 67 percent of the peptide publications it identified used preclinical animal models, most commonly rats (PMID 42578445).

For sermorelin, no animal study appeared among the abstracts retrieved in this research. That is a sampling limit of a single literature search, not evidence that none exist, and this guide does not claim sermorelin lacks animal data.

Safety and Side Effects

The strongest compound-specific safety statement retrieved is FDA's, about ipamorelin. Its category 2 entry states that compounded ipamorelin acetate "may pose risk for immunogenicity for certain routes of administration due to the potential for aggregation or peptide-related impurities," that it "contains unnatural amino acids, which add to the complexity of peptide characterization," and that "a study published in literature identified serious adverse events including death when ipamorelin was administered intravenously for improving gastric motility" (FDA). FDA adds that for other injectable routes it "lacks sufficient information to know whether the drug would cause harm if administered to humans via those routes." FDA does not name the study behind that sentence, and nothing retrieved here identifies it, so this guide quotes FDA and names no trial, no PMID and no count.

Neither registered ipamorelin trial posted a results section, so there is no trial adverse event data to report for either one. That is a gap, not a clean bill of health.

At the class level, and not tied to either of these two specifically, reviews of peptides as a group list "cardiovascular strain, insulin resistance, dyslipidemia, and psychiatric instability" (PMID 41880199) and "cardiovascular complications and metabolic dysfunction such as insulin resistance" (PMID 42578445). One risk is frequently mis-assigned: the congestive heart failure signal in these reviews is attributed to MK-677, also called ibutamoren, which is a different compound. It does not carry over to ipamorelin or sermorelin, and this guide does not carry it over.

Supply quality is its own hazard. Reviews note that unregulated peptide products are "often mislabeled or contaminated" (PMID 41880199), shown concretely by the identification of a black market analogue, Gly-Ipamorelin, confirmed by custom synthesis (PMID 29864719). On unapproved peptides generally, "rigorous human safety data are scarce, and there is potential for serious harm to patients" (PMID 41966639).

For sermorelin, no adverse reaction list was obtained. The GEREF label could not be retrieved, so there is no labeled adverse reaction, warning or contraindication text to quote here. The only regulatory statement retrieved is that FDA independently evaluated the literature and postmarketing data for both GEREF products and determined they "were not withdrawn from sale for reasons of safety or effectiveness" (Federal Register 78 FR 14095). That is a statement about why the drug left the market, not a safety endorsement of current use.

Vietnam Availability Reality

Start with what could not be established, because it matters for what this section is allowed to claim. Vietnam's drug registration databases could not be reached in this research: the Drug Administration site timed out and the national drug database did not resolve. Those are tooling failures, not findings. So this guide does not state that either sermorelin or ipamorelin is, or is not, registered in Vietnam. Anyone who needs that answer should check with the Drug Administration of Vietnam directly.

Among the pharmacy chains, only Nha thuoc Long Chau could be searched cleanly, and its server-rendered search returns no product for either "sermorelin" or "ipamorelin," a total count of zero for both terms, so there is no price to record. Pharmacity and Nha thuoc An Khang could not be evaluated: Pharmacity renders its results in the browser and returned no product data in the server response, and An Khang reset the connection on every request. Those are tooling blocks. They are not the same as a store confirming it carries nothing, and this guide does not read them as absence.

On clinics, no fetched page states that a clinic stocks, sells or administers either compound. One Vietnamese clinic page, MedFit, classifies both compounds the way the English literature does and states that growth hormone secretagogue peptide use for muscle building is "không được khuyến cáo" in Vietnam and that "Hiện chưa có loại thuốc peptide nào được Bộ Y tế phê duyệt cho mục đích tăng cơ bắp," meaning no peptide drug is Ministry of Health approved for muscle gain. That is a clinic's statement, attributed to MedFit and not a Ministry of Health publication, and it advises against use rather than offering the compounds. No published price exists for either compound from any source retrieved here.

What This Comparison Cannot Tell You

An honest comparison names its own edges. Here is what the sources behind this page do not support, so that you can recognize it when a competing page claims otherwise without one.

The Bottom Line

The clearest true difference between sermorelin and ipamorelin is regulatory, not a performance figure. Sermorelin was a licensed drug, GEREF, that its sponsor discontinued in 2008 and FDA withdrew from the US market in 2009, a withdrawal FDA later confirmed was not for reasons of safety or effectiveness (Federal Register 78 FR 14095). Ipamorelin was never approved and now sits in FDA's compounding category 2 with an explicit safety warning (FDA).

The mechanisms differ, a GHRH analogue against a ghrelin receptor secretagogue (PMID 41880199), and the human trial evidence for both is thin and pointed away from the uses people ask about: ipamorelin's registered trials are in post-operative gut recovery with no posted results, and sermorelin's registered use here is a diagnostic growth hormone test.

No trial ranks the two, and this guide does not rank them either. It reports the figures with their evidence level attached and stops there. It does not tell you what to take.

None of this is medical advice. Neither compound is an approved medicine you can fill at a pharmacy for body composition or aging. Talk to a licensed clinician before acting on any of it.

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