Growth HormoneEmerging ResearchResearch Only

Ipamorelin

Also known as: Ipamorelin Acetate, NNC 26-0161

Ipamorelin is a pentapeptide growth hormone secretagogue that acts on the ghrelin receptor (GHS-R1a) in the pituitary gland to stimulate growth hormone release. Unlike other GH secretagogues such as GHRP-6, ipamorelin is highly selective and does not cause significant increases in cortisol, prolactin, or appetite, making it one of the cleanest GH-stimulating peptides available. It produces a dose-dependent GH release pattern that closely mimics natural pulsatile secretion. Ipamorelin is frequently combined with CJC-1295 for synergistic effects on GH output.

Research Score7/10

Growing body of research

Safety Score8/10

Well-tolerated with minimal side effects

Get provider prescribed Ipamorelin

How It Works

Ipamorelin is a selective GH secretagogue that binds to ghrelin receptors on pituitary cells, stimulating GH release without affecting cortisol, prolactin, or ACTH.

Key Benefits

Selective growth hormone release without cortisol spikes
Improved recovery from exercise and injury
Enhanced fat metabolism and body composition
Better sleep quality
Supports collagen synthesis and joint health
Minimal impact on appetite compared to other GH secretagogues

Who May Benefit

Adults seeking GH optimization with minimal side effects
Individuals improving body composition and recovery
People wanting GH benefits without cortisol elevation
Those combining with CJC-1295

Dosage & Administration

Typical Dosage

One to two times daily

Cycle Length

8-12 weeks, with 4-week breaks between cycles

Administration Routes

subcutaneous

Expected Timeline

Sleep and recovery improvements in 2-3 weeks. Body composition changes at 6-8 weeks.

Safety Information

Possible Side Effects

Mild headacheTransient lightheadednessInjection site irritationWater retention (uncommon)

Contraindications

Active cancer or history of malignancyPregnancy or breastfeedingPituitary disordersType 1 diabetes (use with caution)

Dr. Taylor's 2 Cents

“What sets ipamorelin apart is its selectivity and half-life — it stimulates GH release without spiking cortisol or prolactin, which is a problem with older secretagogues like GHRP-6. I combine it with CJC-1295 in most of my GH optimization protocols. Patients love it because it improves sleep almost immediately, and the body composition changes follow within weeks.”

Discuss with Dr. Taylor →

Frequently Asked Questions

What makes Ipamorelin different?

The first truly selective GH secretagogue that does not affect cortisol or prolactin even at high doses.

Is it combined with other peptides?

Frequently combined with CJC-1295 as the gold standard for GH optimization.

What dosage is typical?

200-300 mcg 2-3 times daily via subcutaneous injection, most important dose before bedtime.

Does Ipamorelin cause hunger?

Minimal to no hunger increase, unlike GHRP-6.

How long can I take it?

Typical cycles are 8-12 weeks with periodic breaks.

Published Research

Ipamorelin, the First Selective Growth Hormone Secretagogue

Raun K, Hansen BS, Johansen NL, et al. · European Journal of Endocrinology (1998)

Key Finding: Ipamorelin displayed high GH-releasing potency and did not increase ACTH or cortisol even at doses 200-fold above the ED50 for GH release, making it the first truly selective GH secretagogue.

PubMed →DOI →

Pharmacokinetic-Pharmacodynamic Modeling of Ipamorelin, a Growth Hormone Releasing Peptide, in Human Volunteers

Gobburu JVS, Agersø H, Jusko WJ, Ynddal L · Pharmaceutical Research (1999)

Key Finding: Ipamorelin induced dose-proportional GH release at all dose levels in healthy male volunteers with predictable pharmacokinetics and reliable GH stimulation.

PubMed →DOI →