Muscle & Growth Hormone

Ipamorelin

selective GHRP · ghrelin mimetic

well-tolerated mainstream subQ injection

What it is

Ipamorelin is a five-amino-acid peptide and the cleanest of the growth hormone releasing peptides (GHRPs). It mimics ghrelin (the hunger hormone) at one specific receptor in the pituitary, triggering a clean GH release without affecting cortisol, prolactin, or aldosterone — the side effects that plague older GHRPs like GHRP-2 and GHRP-6.

How it works

Your pituitary gland releases growth hormone in pulses, primarily during deep sleep. Ipamorelin signals the pituitary to release a single clean pulse of GH. Unlike taking exogenous synthetic HGH, this works with your body's natural feedback loops, so you can't suppress your own GH production.

Because it doesn't touch the cortisol or prolactin pathways like older GHRPs, it's safe to dose multiple times daily and to run for extended periods.

It pairs well with a GHRH analog (CJC-1295, Tesamorelin, or Sermorelin) because the two work via different mechanisms and produce a much stronger combined GH release than either alone.

Benefits

Improved sleep quality (especially deep, restorative sleep)
Increased lean muscle mass over months
Better recovery from training
Modest fat loss, particularly visceral fat
Improved skin quality and elasticity
Enhanced bone mineral density (animal evidence)
Anti-aging effects via natural GH/IGF-1 normalization

Timeline

Week 1–2: Improved sleep quality — usually the first noticeable benefit.
Week 3–4: Better recovery from training; reduced soreness.
Week 6–8: Visible body composition changes; energy and mood improvements.
Week 12–24: Peak benefits — lean mass gains, sustained sleep quality, body recomp.

Dosing & titration

Standard dose200–300 mcg, 1–3x daily

Beginner protocol200 mcg pre-bed for 4 weeks, then add a morning dose

Advanced protocol300 mcg 2–3x daily, paired with CJC-1295 or Tesamorelin

TimingEmpty stomach — at least 30 min before food. Pre-bed dose is most important.

Cycle length5 days on, 2 off OR 8–12 weeks on, 4 weeks off to maintain receptor sensitivity

When to titrate upIf sleep and recovery improvements plateau after 4–6 weeks at 200 mcg, increase to 300 mcg or add a second daily dose. Going beyond 600 mcg/day rarely produces additional benefit.

Side effects & risks

Mild head-rush or flushing in the first few minutes after injection
Mild hunger increase (less than other GHRPs)
Tingling in extremities (transient)
Drowsiness when dosed pre-bed (often desired)
Injection site reactions
Long-term high-dose use may slightly raise IGF-1 and have theoretical cancer concerns

Get baseline IGF-1 before starting. Re-check at 12 weeks. If IGF-1 climbs above the upper-normal range, reduce dose. Contraindicated in active malignancy, severe diabetic retinopathy, and uncontrolled diabetes.

Typical price

$60–$120/mo 5–10 mg vial from a 503A compounding pharmacy. Often sold as a CJC-1295/Ipamorelin blend.

Studies

Ipamorelin, the first selective growth hormone secretagogue — Foundational paper introducing the molecule and its clean side-effect profile. PubMed European Journal of Endocrinology, 1998
Pharmacokinetic-pharmacodynamic modeling of Ipamorelin in human volunteers — Established dose-response and GH-release kinetics. PubMed Pharmaceutical Research, 1999
Ipamorelin induces longitudinal bone growth in rats — Demonstrated GH/IGF-1-driven growth effects. PubMed European Journal of Endocrinology, 1999
Ipamorelin counteracts glucocorticoid-induced decrease in bone formation — Showed bone-protective effects in stressed animals. PubMed European Journal of Endocrinology, 2001
Growth hormone secretagogues: history, mechanism of action, and clinical development — Modern review of the entire GHRP/GHS family. JCSM Rapid Communications Wiley, 2020

Educational reference only. Not medical advice. Ipamorelin is not FDA-approved as a drug. Any use should be under guidance of a licensed prescriber.