All dosing information on this page is research-context only, sourced from published peer-reviewed literature. Ipamorelin is not approved by the FDA, EMA, or any other regulatory agency for human use. This site does not sell any product and does not provide medical advice.
Research Doses by Species and Study Context
The following doses reflect what was administered in published peer-reviewed research. They are presented for research literature context only.
| Study / Year | Species | Dose | Route | Context |
|---|---|---|---|---|
| Raun et al., 1998 [1] | Rat (anesthetized) | 80 nmol/kg (ED50) | IV | GH selectivity characterization |
| Raun et al., 1998 [1] | Swine (conscious) | 2.3 nmol/kg (ED50) | IV | GH selectivity characterization |
| Johansen et al., 1999 [2] | Rat (adult female SD) | 18–450 mcg/day ÷ 3 | SC injection | Longitudinal bone growth (15 days) |
| Svensson et al., 2000 [4] | Rat (young female SD) | 0.5 mg/kg/day | SC minipump | Bone mineral content (12 weeks) |
| Andersen et al., 2001 [3] | Rat (adult female Wistar) | 100 mcg/kg ×3/day | SC injection | Glucocorticoid bone rescue (3 months) |
| Aagaard et al., 2009 [7] | Rat (prednisolone-treated) | 0.5 mg/kg/day | SC injection | Nitrogen balance / urea synthesis |
| Venkova et al., 2009 [8] | Rat (POI model) | 1 mg/kg (acute); 0.1–1 mg/kg ×4/day | IV | GI motility / postoperative ileus |
| Greenwood-Van Meerveld et al., 2012 [9] | Rat (POI model) | 0.014–0.14 mcmol/kg | IV | Gastric emptying |
| Beck et al., 2014 [10] | Human (N=114) | 0.03 mg/kg ×2/day | IV infusion | Phase 2 / postoperative ileus (up to 7 days) |
Pharmacokinetics
Gobburu et al. (1999) conducted pharmacokinetic-pharmacodynamic modeling of ipamorelin in healthy human volunteers receiving single IV doses across multiple dose levels.[12] Key parameters:
| Parameter | Value | Source |
|---|---|---|
| Terminal half-life | ~2 h | Gobburu 1999 [12] |
| Clearance | 0.078 L/h/kg | Gobburu 1999 [12] |
| Volume of distribution (Vss) | 0.22 L/kg | Gobburu 1999 [12] |
| Time to peak GH (Tmax) | ~40 min | Gobburu 1999 [12] |
| PK linearity | Linear (dose-proportional) | Gobburu 1999 [12] |
| Plasma clearance vs GHRP-6 | ~5× lower | Johansen PB 1998 [11] |
| Biliary/urinary excretion (intact) | 60–80% of dose | Johansen PB 1998 [11] |
| Intranasal bioavailability (rat) | ~20% | Johansen PB 1998 [11] |
GH returned to negligible levels within 2–3 hours of dosing, consistent with the single discrete GH pulse per administration that characterizes ipamorelin's receptor pharmacology.[12]
Schematic ipamorelin PK profile in human volunteers: GH peak at ~40 min, exponential decay to baseline within 2–3 h. Linear dose-proportional PK (Gobburu et al., 1999).
The Aib N-terminal modification that confers metabolic stability (protecting against N-terminal peptidase cleavage) is a design feature of the ipamorelin scaffold that distinguishes it from GHRP-1, its parent peptide, and contributes to the lower plasma clearance relative to GHRP-6.[11]
Routes Studied in the Published Literature
- Intravenous bolus: primary route in human clinical pharmacology (Gobburu 1999) and the Phase 2 trial (Beck 2014); also used in rat acute pharmacology (Raun 1998, Venkova 2009, Greenwood-Van Meerveld 2012)
- Subcutaneous injection: primary route in most rodent chronic administration studies (Johansen 1999; Andersen 2001; Aagaard 2009)
- Subcutaneous continuous infusion (osmotic minipump): used by Svensson et al. (2000) for the 12-week bone mineral content study
- Intranasal: characterized pharmacokinetically in rats (Johansen et al. 1998); approximately 20% bioavailability
- Intraperitoneal: used in ferret cisplatin model (2024) and mouse adiposity study (Lall 2001)
No oral human bioavailability data have been published for ipamorelin. The oral bioavailability work in the structure-activity literature relates to analog NNC 26-0235, not to ipamorelin itself.[13]
Reagent-Grade Sourcing: What Researchers Should Verify
Research-grade ipamorelin is distributed as a lyophilized powder and is characterized by the following benchmarks, as noted in the FDA 503A compounding nomination docket (FDA-2024-N-4188) and standard analytical chemistry practice:[16]
- HPLC purity: ≥98% by reversed-phase HPLC (peak area method)
- Identity confirmation: LC-MS molecular weight match to 711.86 Da (C38H49N9O5)
- Amino acid analysis: confirming the pentapeptide sequence (
Aib-His-D-2-Nal-D-Phe-Lys-NH2) - Storage: lyophilized powder at −20°C long-term; reconstituted at 4°C for short-term research use
- COA documentation: lot number, purity percentage, MS identity confirmation, and storage specifications per lot
Third-party COA documentation — analytical data generated by an independent laboratory rather than the vendor's internal QC — provides the most reliable evidence of reagent quality. Researchers should request the actual HPLC chromatogram and LC-MS spectrum rather than only the purity percentage summary.
Preparations with purity below 98% or without MS identity confirmation should not be used in mechanistic research, as impurity profiles at unknown concentrations confound dose-response interpretation. Quality of commercially available research-grade preparations varies widely.