What is Ipamorelin?
Ipamorelin is a pentapeptide ghrelin mimetic developed to selectively stimulate growth hormone release. Unlike older GHRPs (GHRP-2, GHRP-6), it does not significantly elevate cortisol, prolactin, or aldosterone, making it a 'clean' option in GH research protocols.
Mechanism of action
Ipamorelin binds the growth hormone secretagogue receptor (GHS-R1a) in the anterior pituitary and hypothalamus. This triggers GH release in a pulse pattern similar to endogenous ghrelin, while sparing the HPA axis.
Researched benefits
- Selective GH pulse without cortisol or prolactin elevation
- Improved sleep depth in user reports
- Lean-mass and recovery signals in animal work
- Bone density support in preclinical models
Researched dosage
Most research protocols use 100–300 mcg administered 2× per day via subcutaneous injection. Research protocols frequently use 100–300 mcg, 2–3× daily, with pre-bed dosing emphasized to support natural overnight GH release.
A typical cycle runs 8 weeks on, then 4 weeks off before reassessment.
Use the calculator below to convert your target Ipamorelin dose into exact insulin-syringe units.
Reconstitution & storage
A standard 5 mg vial reconstituted with 2 mL of bacteriostatic water yields 2500 mcg/mL. Lyophilized stable at 2–8°C; refrigerate after reconstitution and use within 30 days.
Side effects & considerations
- Mild flushing after injection
- Increased appetite (ghrelin-mimetic effect)
- Drowsiness if dosed near bedtime
Ipamorelin stacks
- Synergistic GH Pulse — paired with CJC-1295. Combined GHRH + GHRP signaling. Pairs the pituitary-priming effect of CJC-1295 (GHRH) with the secretagogue burst of Ipamorelin for a larger, cleaner GH pulse.
Selected research
- Ipamorelin, the first selective growth hormone secretagogue — European Journal of Endocrinology, 1998
- Effects of Ipamorelin on bone metabolism — Bone, 2000