Pralmorelin, KP-102, GHRP Kaken 100 (Japan)
A six-amino-acid synthetic peptide that activates the ghrelin (hunger hormone) receptor, causing a strong, short pulse of growth hormone. In Japan a single IV dose is used to diagnose GH deficiency.
Category 2 is FDA’s list of bulk substances that may present significant safety risks in compounding. The 503A bulks list adds substances that pharmacies may compound with. Advisory committee votes are advice; FDA makes the final decision. Sport status follows the WADA Prohibited List in force since January 1, 2026; athletes should confirm with their anti-doping organization. Checked October 5, 2026. Status of every compound.
GHRP-2 (pralmorelin) binds the growth hormone secretagogue receptor, the receptor for the hunger hormone ghrelin, and, the Japanese label says, acts mainly through the hypothalamus, the brain area that controls the pituitary, to release growth hormone. After an IV dose, GH in the blood peaks within 15–60 minutes. In rats, the effect weakened when the pituitary was removed or the hypothalamic areas that control it were damaged.
LabelBased on the product label.
Whether repeated doses do anything lasting is unclear: in children with GH deficiency, 8 months of daily injections (6 children) and a 48-week nasal spray (126 children) raised GH secretion but not IGF-1.
GHRP Kaken 100 (Japan)
Diagnostic test only: one 100 mcg IV dose after an overnight fast (children aged 4–17: 2 mcg/kg, up to 100 mcg). Not a treatment regimen.
Tanaka 2014
Nasal spray, 50–200 mcg (by body weight) twice daily for 48 weeks in children with GH deficiency; no growth benefit over placebo.
100 mcg per injection (often framed as about 1 mcg/kg), 1–3× daily on an empty stomach; some guides go up to 200–300 mcg.
12 weeks on, 4 off, shown over 26 weeks
The ways GHRP-2 is most often run, each tagged with where it comes from.
Given fasting and lying down, with blood drawn over the next hour. A peak GH of 9 ng/mL or less (with current GH assay standards) points to severe adult GH deficiency.
Not tested as repeated injections in any published trial. Guides treat about 1–2 mcg/kg as a ceiling above which GH rises little more.
In 17 older adults, GH output stayed about 1.8× higher and IGF-1 rose to a plateau (Bowers 2004). Not comparable to injections.
126 children with GH deficiency; height gain was no better than placebo (Tanaka 2014).
0.3–3 mcg/kg. Japanese label: 0.3–3 mcg/kg IV was given to healthy men in the drug-level study; the test dose is 2 mcg/kg (max 100 mcg) for children 4–17 and a flat 100 mcg for adults. Infusion trials ran at 1 mcg/kg per hour. None are subcutaneous injection doses.
Community use is subcutaneous injection (under the skin), rotating sites, on an empty stomach. The approved Japanese test is a single IV injection; trials also used a nasal spray and continuous infusions.
No published guidance. Skip the missed dose and take the next one on schedule; don’t double up.
GH peaks: mean 84.6 mcg/L in healthy adults vs 1.36 in adults with GH deficiency.
TrialHealthy men ate 35.9% more at a buffet meal than on saline, and GH rose about 13-fold.
TrialGH output was 1.8× the saline level at days 14 and 30, and IGF-1 rose to a steady plateau from day 1.
TrialHeight compared with peers (SD score) changed 0.02–0.03 vs 0.07 on placebo, and IGF-1 didn’t change.
TrialHot or flushed feeling (16% in Japanese trials)
Starts right after the dose and passes. Reported as mild in the test studies.
Stomach rumbling or nausea (rumbling in 19 of 135 people in the 2007 test study)
Short-lived after IV dosing; every side effect in that study was mild or moderate and passed without treatment. Persistent nausea or belly pain needs a doctor.
Hunger and eating more
Expected ghrelin-receptor effect (36% more food in one study). Dosing away from meals may help; stop if it’s a problem.
Higher blood sugar or insulin needs
FDA lists higher insulin needs among reported events. Check fasting glucose, especially with prediabetes or diabetes.
Infection, pancreatitis (reported to FDA, causality not established)
Mostly from studies of very sick hospital patients. Severe belly pain that won’t go away needs urgent care.
Get medical help for hives, face or throat swelling or trouble breathing, severe belly pain that won’t go away, or signs of very high blood sugar (extreme thirst, frequent urination, confusion).
From its label, human studies and precautions based on how it works, most important first.
Only interactions stated on a product label or measured in a human study are listed.
Label: a product label rules it out, warns about it or lists the interaction. Trial: seen in human studies, or a group those studies left out. Precaution: follows from how it works or from a related drug, and hasn’t been tested. This isn’t a complete list: a pharmacist or doctor can check a specific medicine or condition.
Common pairing: a GHRH analog plus a GHRP. In older adults, GHRP-2 plus natural GHRH released more GH than either alone (Bowers 2004), but the CJC-1295 combination was never tested.
5 key published human studies, with how many people took part. Animal studies aren’t listed here.
Height SD score (height compared with peers) changed 0.07 on placebo vs 0.03 (low dose) and 0.02 (high dose), with no difference in IGF-1: no growth benefit.
Tanaka et al., Clin Pediatr Endocrinol 2014, PMID 25374440
Peak GH averaged 84.6 mcg/L in 77 healthy adults vs 1.36 in 58 patients; a 15 mcg/L cutoff (9 with current assay standards) separated the groups, and 40% had short-lived, mostly mild side effects such as flushing.
Chihara et al., Eur J Endocrinol 2007, PMID 17609397
GH secretion was over 3× the saline level on day 1 and 1.8× on days 14 and 30; IGF-1 rose to a steady plateau from day 1 and safety tests stayed normal.
Bowers et al., J Clin Endocrinol Metab 2004, PMID 15126555
IGF-1 and GH-dependent binding proteins reached near-normal levels from day 2; osteocalcin (a bone-building marker) rose 19% vs a 6% fall on placebo, and the urea/creatinine ratio fell, suggesting less protein breakdown.
Van den Berghe et al., J Clin Endocrinol Metab 1999, PMID 10199772
Every man ate more: intake was 35.9% higher than on saline (32.5 vs 24.2 kcal/kg, p=0.008).
Laferrère et al., J Clin Endocrinol Metab 2005, PMID 15699539
As a medicine, GHRP-2 is approved only for a one-time IV test for GH deficiency, validated in 135 adults. Repeated use has been studied in a few trials: 8 months of injections in 6 children, a 30-day infusion in 17 older adults, and a 48-week nasal spray in 126 children that didn’t improve growth. Long-term injections in healthy adults, long-term safety and product purity are untested.
| Vial | Water | Common dose | Draw | Strength | Action |
|---|---|---|---|---|---|
| 5 mg | 2.5 mL | 100 mcg | 5 units (0.05 mL) | 2 mg/mL | |
| 10 mg | 5 mL | 100 mcg | 5 units (0.05 mL) | 2 mg/mL |
With 2.5 mL in a 5 mg vial (or 5 mL in a 10 mg vial, if it holds that much), each 100 mcg is 5 units on a U-100 syringe. The Japanese test vial is a different product: 100 mcg dissolved in 10 mL of saline for one IV dose.
Syringe units for common doses at different water volumes. Select a cell to open it in the calculator.
| Dose | Water added | |||
|---|---|---|---|---|
| 1 mL | 2 mL | 2.5 mL | 3 mL | |
| 100 mcg | ||||
| 150 mcg | ||||
| 200 mcg | ||||
| 250 mcg | ||||
| 300 mcg | ||||
U-100 insulin syringe: 100 units is 1 mL. Draws over 100 units show in mL. Faded values are under 2 units, which is hard to measure. Check that your vial holds the larger volumes.
Every compound side by side: the half-life chart and the storage chart.
A six-amino-acid synthetic peptide that activates the ghrelin (hunger hormone) receptor, causing a strong, short pulse of growth hormone. In Japan a single IV dose is used to diagnose GH deficiency.
GHRP-2 (pralmorelin) binds the growth hormone secretagogue receptor, the receptor for the hunger hormone ghrelin, and, the Japanese label says, acts mainly through the hypothalamus, the brain area that controls the pituitary, to release growth hormone. After an IV dose, GH in the blood peaks within 15–60 minutes. In rats, the effect weakened when the pituitary was removed or the hypothalamic areas that control it were damaged. Whether repeated doses do anything lasting is unclear: in children with GH deficiency, 8 months of daily injections (6 children) and a 48-week nasal spray (126 children) raised GH secretion but not IGF-1.
Not approved in the US or EU. In Japan, pralmorelin (GHRP Kaken 100) has been approved since 2004 as a single IV dose to diagnose growth hormone deficiency, not as a treatment; its package insert was last revised in July 2025. Still in FDA Category 2 for outsourcing facilities (503B) for injectable and nasal use as of April 2026, over immunogenicity risk and reported serious events; other routes are still under evaluation. For pharmacy compounding (503A) it is in Category 3, nominated without adequate support (May 2026 list). Not on the July 2026 advisory committee agenda.
From the label (GHRP Kaken 100 (Japan)): Diagnostic test only: one 100 mcg IV dose after an overnight fast (children aged 4–17: 2 mcg/kg, up to 100 mcg). Not a treatment regimen. From human studies (Tanaka 2014): Nasal spray, 50–200 mcg (by body weight) twice daily for 48 weeks in children with GH deficiency; no growth benefit over placebo. These are the amounts sources reference, not recommendations.
There’s no single right amount, because the water only sets the strength. With 2.5 mL of bacteriostatic water in a 5 mg vial, the strength is 2 mg/mL, so 100 mcg is 5 units on a U-100 insulin syringe. More water makes small doses easier to measure. The dose chart above shows other volumes.
Pregnancy or possible pregnancy: Ruled out by the Japanese label (GHRP Kaken 100). Breastfeeding: The Japanese label says to weigh the test’s value against breastfeeding; in rats, the drug passed into milk. A pituitary tumor: The label notes pituitary apoplexy, sudden bleeding or tissue death in the gland with vision problems, headache and vomiting, reported when a similar drug was given to people with pituitary tumors. The “Who should avoid it” section lists 4 more groups and 3 interactions.
About 25 to 40 minutes, according to the prescribing information. Elimination half-life of 0.42–0.69 hours after IV doses of 0.3–3 mcg/kg in 18 healthy men; a study in 10 children given 1 mcg/kg IV found 0.55 hours.
Before mixing: Japanese test vials: at or below 10 °C, not frozen; shelf life 3 years. Dissolved in 10 mL of saline just before the test and used once. Keep out of light once the box is opened.
Yes. S2.2.4 growth hormone releasing factors: GH-releasing peptides (GHRPs), with GHRP-2 (pralmorelin) named. Banned at all times.
Yes. The human studies section lists 5 published studies. The largest, from 2007, included 135 people. Peak GH averaged 84.6 mcg/L in 77 healthy adults vs 1.36 in 58 patients; a 15 mcg/L cutoff (9 with current assay standards) separated the groups, and 40% had short-lived, mostly mild side effects such as flushing.
For the protocol details
For how it works, who should avoid it and the limits of the evidence
Doses tagged Community come from public dosing guides and user reports, checked against at least two of them. Those sites aren’t named here because many of them sell peptides or earn commissions on them.