Quick answer: there is no established ipamorelin dosage. In published human studies, ipamorelin was given only by IV: single infusions of 4.21 to 140.45 nmol per kg (roughly 3 to 100 mcg per kg) in healthy men, and 0.03 mg per kg twice daily after bowel surgery.[1][2] FDA found no human data at all for injecting it under the skin, which is how it is usually sold.[4]
This guide covers each human dose studied, what those doses did, why online “protocols” have no trial basis, and what to ask a clinician. For the full background, see our ipamorelin profile and the growth hormone peptides hub.
What ipamorelin is
Ipamorelin is a five-amino-acid peptide developed at Novo Nordisk in the 1990s. It mimics ghrelin and triggers a pulse of growth hormone from the pituitary gland.[6] In pigs, it released growth hormone about as strongly as the older peptide GHRP-6, but without raising the stress hormones ACTH and cortisol.[6] No FDA-approved product contains it, and FDA found no listing for it in the European, Chinese, Indian or Japanese pharmacopoeias.[4]
Because there is no approved product, there is no label dose. Everything below comes from research studies.
Ipamorelin doses used in human studies
| Study | Who | Dose | Route |
|---|---|---|---|
| Pharmacokinetic study[1] | Healthy men, 8 per dose level | 4.21, 14.02, 42.13, 84.27 or 140.45 nmol/kg, once | 15-minute IV infusion |
| Phase 2 surgery trial (published)[2] | 114 adults after bowel resection | 0.03 mg/kg twice daily, up to 7 days | IV infusion |
| Dose-finding surgery trial (unpublished)[3] | 320 adults after bowel resection | 0.03 mg/kg twice daily, 0.06 mg/kg twice daily, or 0.06 mg/kg three times daily | IV infusion |
Converting the study doses
Researchers often report peptide doses in nanomoles per kilogram. Ipamorelin’s molecular weight is about 711.9,[5] so the five healthy-volunteer doses work out to roughly 3, 10, 30, 60 and 100 mcg per kg. The surgery trial’s 0.03 mg per kg equals 30 mcg per kg, the middle of that range.[2]
These were research doses given into a vein under hospital supervision, not a guide for anyone using ipamorelin.
What the healthy-volunteer study found
The 1999 study is the only published measure of how ipamorelin behaves in healthy people:[1]
- One burst, not a steady rise. Each infusion caused a single episode of growth hormone release, peaking at about 0.67 hours (40 minutes), then declining.
- Short half-life. Ipamorelin’s terminal half-life was about 2 hours, and blood levels rose in proportion to the dose.
- People responded differently. Variation between individuals in growth hormone response was larger than variation in drug levels.
FDA’s review adds that growth hormone fell to very low levels by about 6 hours, that the lowest dose produced negligible growth hormone and was left out of the analysis, and that the study did not report adverse events.[4] FDA’s account also describes 6 men on ipamorelin and 2 on placebo per dose group, which differs slightly from the paper’s summary.
What the surgery trials found
Helsinn Therapeutics tested IV ipamorelin to speed recovery of gut function after bowel surgery (postoperative ileus).
- Published phase 2 trial: 0.03 mg per kg twice daily did not significantly shorten the time to a tolerated solid meal: a median of 25.3 hours versus 32.6 hours on placebo (p = 0.15). There were no significant differences in any key or secondary efficacy analysis.[2]
- Dose-finding trial: tested two higher dose schedules in 320 patients and was completed in May 2014, but no results have been posted to the registry.[3]
So the only human dose with published efficacy results did not work for the condition tested. For side effects in that trial, see our ipamorelin side effects guide.
Doses under the skin, by mouth or nose
Most ipamorelin sold today is meant for injection under the skin. Here is what is known about other routes:
- Under the skin (subcutaneous): FDA said it found no pharmacokinetic, pharmacodynamic or safety data in humans for this route.[4]
- Nasal: in rats, about 20% of a nasal dose was absorbed.[7] No human nasal dosing study has been published.
- Animal doses: studies in pigs, rats and mice used doses per kilogram that cannot be converted directly to people.[6][11] In mice, twice-daily injections under the skin increased body fat and food intake, the opposite of the fat loss often claimed.[11]
Timing, frequency and stacking
Because the half-life is about 2 hours and each dose causes a single growth hormone pulse, any dosing schedule would need repeated doses to keep an effect.[1] The surgery trials used two or three IV doses a day.[2][3] No human study has tested:
- Bedtime dosing for sleep.
- Daily or weekly cycles for muscle or fat loss.
- Combining ipamorelin with CJC-1295 or other peptides.
For what is known about those combinations, see CJC-1295 and ipamorelin and tesamorelin with ipamorelin.
Legal status affects who can supply it
- Outsourcing facilities (503B): FDA lists ipamorelin acetate in category 2, substances that may present significant safety risks, since September 29, 2023.[9]
- Traditional pharmacies (503A): on October 29, 2024, FDA’s Pharmacy Compounding Advisory Committee voted 0 to 12, with one abstention, against adding ipamorelin to the list of bulk substances these pharmacies may use. FDA had proposed not adding it.[8][4]
In practice, this means there is no FDA-approved or FDA-endorsed source of ipamorelin, and a clinician who suggests it is working without trial-based dosing. For how ipamorelin compares with other options, see sermorelin vs ipamorelin.
Questions to ask a clinician
- Which human study is this dose based on, given that none tested injections under the skin?
- What do you expect it to do for me, and how will we measure it?
- Is there an FDA-approved treatment for my goal instead?
- Which blood tests (IGF-1, glucose, potassium) will you monitor?
- Who makes the product, and how is it tested for purity and sterility?
For help reading units on any prescription, see our peptide calculator. It explains the math; it does not recommend a dose. Talk to a licensed clinician before using any growth hormone-related product.
