Ipamorelin

Typical use cases

Dosing guidelines

Titration

Reports commonly describe starting at the low end (~100 mcg) and increasing gradually toward ~200-300 mcg as tolerated; this is educational, not a recommendation to change any dose.

Reconstitution

Lyophilized powder is typically reconstituted with bacteriostatic water (e.g., ~2-3 mL added to a 10 mg vial), injected slowly down the vial wall and gently swirled (not shaken) until fully dissolved.

Injection sites

Subcutaneous injection, commonly into abdominal subcutaneous fat (rotating sites); thigh and upper-arm fat also used.

Storage & handling

Lyophilized powder stored refrigerated (2-8°C) or frozen and kept out of light; once reconstituted, refrigerate at 2-8°C, do not refreeze, and discard within roughly 3-4 weeks.

Side effects

• Injection-site reaction (redness, itching, swelling) Mild · Common
• Headache Mild · Common
• Transient flushing or head-rush after injection Mild · Uncommon
• Lightheadedness / dizziness Mild · Uncommon
• Water retention or transient peripheral edema Moderate · Uncommon
• Increased appetite (ghrelin-receptor activity) Mild · Uncommon

Research summary

Ipamorelin was first described by Raun and colleagues in 1998 (Novo Nordisk, development code NNC 26-0161) as "the first selective growth hormone secretagogue." Preclinical work in rats and swine showed it releases GH with potency and efficacy comparable to GHRP-6, but unlike GHRP-6 and GHRP-2 it did not meaningfully elevate ACTH or cortisol even at doses well above the GH-releasing effective dose — the basis of its "selectivity" reputation. Mechanistically it is an agonist at the growth hormone secretagogue receptor type 1a (GHS-R1a, the ghrelin receptor) on pituitary somatotrophs, driving Gq/PLC signaling, IP3-mediated calcium release, and GH exocytosis in discrete pulses. A 1999 rat study reported dose-dependent increases in longitudinal bone growth and body weight, but the authors emphasized that clinical relevance would require future human trials. The most advanced clinical development was as a candidate for postoperative ileus (Helsinn Therapeutics), supported by rodent data showing repeated dosing increased fecal output, food intake, and weight gain; this program reached Phase II but was reportedly discontinued for lack of efficacy at that indication. As a result, ipamorelin is not an approved drug anywhere and is handled as a research chemical, and it appears on anti-doping prohibited-substance lists. Direct controlled human evidence for the body-composition, recovery, and "anti-aging" outcomes commonly discussed in community settings is limited, and long-term human safety data are sparse; most widely cited claims rest on pharmacology and animal studies rather than large randomized human trials.

Key references

• https://academic.oup.com/ejendo/article-abstract/139/5/552/6748390
• https://pubmed.ncbi.nlm.nih.gov/10373343/
• https://pubmed.ncbi.nlm.nih.gov/19289567/
• https://pubchem.ncbi.nlm.nih.gov/compound/Ipamorelin
• https://en.wikipedia.org/wiki/Ipamorelin

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