Japan-approved GH diagnostic sold as a vial; hunger, cortisol and prolactin spikes, GH axis.
Safety tier
Avoid
strict bar
Positive
39%
of 7 reports
Per month
≈ €18–45
estimate
Rank
#56
of 61 research peptides
At a glance
Access
Grey market
InjectionFelt in 10–30 min, lasts 1–3 h
15 min1 h6 h1 day1 week
Strict case
GH/IGF-1 axis elevation with cortisol and prolactin spikes; FDA notes raised insulin needs and deaths in critically ill subjects.
Best effects
Acute GH pulse (peaks within 60 minutes) · hunger within minutes · better sleep for some · faster gastric emptying
Downsides
Intense hunger, shakiness if a meal is skipped · weakness, tiredness or nausea for up to an hour after injection · water retention and bloating · two to four injections a day timed around meals
Typical use
Users: 100-300 mcg subq 1-3x/day, fasted, 20-30 minutes before eating, often with mod-GRF. Diagnostic label: 100 mcg IV once (2 mcg/kg in children).
Stacked with
Stacked with
CJC-1295 / mod-GRF(1-29): The classic pairing: a GHRH analogue amplifies the GHRP pulse, injected together 2-3 times a day before meals. · Retatrutide or other GLP-1 agonists: Some users add a GHRP to blunt GLP-1 appetite suppression and speed gastric emptying. · Ipamorelin: Often recommended in its place: same receptor, little cortisol or prolactin effect.
Safety
Watch
GH/IGF-1 axis elevation (glucose, theoretical neoplasm promotion) · Acute ACTH/cortisol and prolactin rises, comparable to a CRH challenge for cortisol (Arvat 1997) · FDA category 2 (2023): reports of increased insulin requirement, pancreatitis, infection and deaths of critically ill study subjects, causality not established · Grey-market vials: aggregation and peptide-impurity immunogenicity concerns (FDA); GHRP-2 also turns up undeclared in other grey-market products
Tier by safety barStrict AvoidBalanced CautionEvidence only Caution
Seen harm1 of 3
Mechanism2 of 3
Data gap1 of 3
Silent harm3 of 3
Product3 of 3
Never if
Pregnancy or possible pregnancy (contraindicated on the Japanese label) and breastfeeding · Active or past cancer · Diabetes, prediabetes or insulin use · Pituitary tumours, including prolactinoma · Cushing's syndrome or other cortisol excess · Critical illness · Children and teenagers (no benefit on growth in a 48-week trial)
The feared harms are IGF-1-driven tumour promotion, which is silent and delayed and counts as 3 under the rubric even though theoretical, and worsening glucose control, which would show on a blood test (a 2). Hunger, nausea and flushing are immediate but not the concern. Renehan et al. 2004: IGF-I and cancer risk ↗
Seven first-hand reports, too few to judge. The consistent effect is a strong hunger spike within minutes, sometimes with weakness, tiredness or nausea for up to an hour, and one user had to eat constantly to keep blood sugar up. Sleep is 'amazing' for one user and unchanged for another. Two users rate it positively (muscle kept on a cut, appetite easier to manage than GHRP-6); one switched to CJC-1295/ipamorelin and preferred it. Most discussion threads push people toward ipamorelin or plain GH instead, citing GHRP-2's cortisol and prolactin effect. Felt nothing: 1 of 7 reports felt nothing; too few reports to put a rate on it..
GHRP-2 has no noticeable effect on my sleep, ipa helps, GHRP-6 makes me drowsy for about half an hour, and then I'm wide awake.
NothingSleep · Injection
compared with ipamorelin (helps sleep) and GHRP-6 (disrupts it)
Studies
Evidence
Approved drug in Japan (2004) only as a single 100 mcg IV test for GH deficiency; no trial shows benefit from repeated dosing, and a 48-week placebo-controlled pediatric trial found no growth effect
Caveat
Japan's approval covers one IV dose under supervision, not daily injections. The repeated-dose trials are in children and ran intranasally; no adult chronic-use safety data exist. One user got nausea rather than hunger, and a commenter suggested the vial might hold something else.
The peptide's chain of amino acids from its start (the N-terminus) to its end, one bead and one letter for each: A alanine, C cysteine, D aspartic acid, E glutamic acid, F phenylalanine, G glycine, H histidine, I isoleucine, K lysine, L leucine, M methionine, N asparagine, P proline, Q glutamine, R arginine, S serine, T threonine, V valine, W tryptophan, Y tyrosine. A modification such as an N-acetyl cap or a C-terminal amide changes how long it lasts in the body. Length tells related peptides apart, from a two-residue dipeptide like carnosine to a 43-residue protein like thymosin beta-4, and predicts neither effect nor safety.
Report grades
Every first-hand Reddit or X report is graded on its own, from glowing through positive, mixed, nothing and negative to bad reaction, and the bar shows how those grades split. Posts that look vendor-adjacent stay on the peptide's page but are left out of the counts.
GlowingPositiveMixedNothingNegativeBad reaction
% positive
The share of a peptide's graded Reddit and X reports that are glowing or positive, vendor-adjacent posts left out. A peptide with few reports is pulled toward the average of all reports, as if it had eight average ones besides its own, so two glowing posts cannot top the list. Peptides rank by this figure, those with no graded report yet after those with one, and Avoid ones after every other entry.
Researcher estimate
No first-hand report of this peptide has been graded yet, so the figure is the researchers' own rating out of 10 from what they read about it. It ranks after every peptide with graded reports until its own arrive.
Safety tier
Each peptide is tiered Clean, Caution or Avoid from its five risk axes under the chosen safety bar. An Avoid peptide carries a real risk of harm, a plausible route to serious harm rather than mere unpleasantness, so it stays listed with the reason but ranks behind every other entry, however good its reviews.
Safety bar
The safety bar sets how much risk it takes to rate a peptide Avoid. Strict: out on any serious mechanism with little human data, or any documented serious harm. Balanced: out on documented serious harm (unless it is obvious, reversible and from a regulated product), or a serious mechanism whose harm would be silent with no human data at all. Evidence only: out only on documented serious harm in humans that is lasting, delayed or from grey-market product.
Seen harm
Documented serious adverse events in humans, from 0 for none despite real exposure to 3 for deaths or several well-documented serious harms. Serious means a hospital or emergency visit or harm lasting weeks, so a headache or a bad night does not count.
Mechanism
A plausible biological route to serious harm at the doses people use, such as growth-factor signalling, hormone-axis suppression, heart or blood-pressure effects or immune activation. It runs from 0 when none is known to 3 when a dangerous pathway has been shown in living animals.
Data gap
How little human safety data exists for the molecule actually sold, from 0 for an approved drug with large trials and years of use to 3 for no human safety data at all. A modified analogue does not inherit its parent's trials.
Silent harm
Whether the feared harm would show quickly or stay hidden, from 0 when it is obvious and goes on stopping to 3 when it is silent and delayed, like tumour promotion or slow organ damage. User reports cannot reveal a harm that takes years to appear, so a high score here limits what good reviews can tell you.
Product
The risk of what people actually buy, from 0 for a regulated pharmacy or supplement product taken by mouth or on the skin to 3 for a grey-market injectable. In one dataset of 6,441 grey-market samples, 42–71% failed basic quality criteria and 15% carried endotoxin; taken by mouth or in the nose, a pack avoids the injection risks.
Evidence
The strongest kind of study behind the peptide's effects, from an approved drug through human controlled trials and small human studies to animal work or nothing of its own. Animal results often fail to carry over to people.
Access
How people get it: as an approved drug, a compounded prescription, an over-the-counter supplement or from the grey market, where nobody checks the vial. The channel decides both the legal position and the risk of a bad batch.
Price per month
Thirty days of the typical dose, from its low end to its high end, priced at the listing a careful buyer would choose: in stock, from a shop scoring 4 of 5 on trust (third-party tested where no score is set), failing that 3, a pure pack before a blend, a European shop first, then the cheapest per mg. The range is the dose's, not the shops'. A per-dose amount counts once a day unless the dose says otherwise. Prices are in euros at ECB rates of 2026-10-29, before shipping; the shop table keeps each listing's price per mg, per gram for bulk supplements. Where no listing can be priced the researchers' own estimate stands in, and says so.
Dose users report
The middle half of the daily doses stated in at least five first-hand reports, vendor posts left out. Where its middle sits more than twice above or below the declared dose, the month is priced at it as well, since what people take is what they pay for.
Shop trust
Each shop's trust on a 1–5 scale, read from its testing and its reputation: 1 for serious red flags (fabricated COAs, scam reports, impersonation, a closed shop), 2 for no public testing, a new shop or active complaints such as seized parcels, 3 for its own COAs or a short track record, 4 for verified third-party testing or a strong reputation, and 5 for third-party batch reports that name the shop, with years of good independent reputation. A shop without a score counts third-party batch testing as 4, its own COAs as 3 and no public tests as 2.
Best value
Within a category or a goal, a peptide that no other beats on both counts: none is rated more positively for the same or a lower monthly price, and none costs less for the same or a higher rating. The chart joins these into the best-value line; the cheapest of them and the best-rated of them both make it, so the line spans the trade-off from cheap to best. Avoid entries never count, and a peptide needs both a % positive and a price to be compared.
Testing
Whether the shop publishes lab results: third-party tested means an independent lab checks each batch, own COA means the shop's own certificate of analysis, and no public tests means neither. A certificate shows purity, not safety.
Added peptide
Some packs sold under one peptide's name hold a second one, such as 5 mg GHK-Cu in a nasal kit, stated only in the description. Sprayed in the nose or injected it reaches the blood like an injection, so it carries the risk of that route and is tiered as the injectable form, whatever its tier on the skin. A pack whose page gives no contents list may hold more than its name.