Side-by-side · Research reference

GLP-1 (7-37)vsIpamorelin

Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.

AHuman-MechanisticHUMAN-REVIEWED16/43 cited

BPhase 1HUMAN-REVIEWED21/57 cited

GLP-1 (7-37)

Incretin Hormone · Native Peptide

~2 minHalf-lifeAlavi 2021 Ding 2017

3297.7 DaMolecular weightAlavi 2021

1922Discovery year

Research use only · IV/SC in experimental settings

Ipamorelin

Selective GHRP · Ghrelin Mimetic

200–300 mcgPer doseRaun 1998

Phase 1Evidence levelRaun 1998 Sigalos 2018

~2 hrHalf-lifeRaun 1998

SQ · Multiple sites · 1–3×/day

01Mechanism of Action

Parameter

GLP-1 (7-37)

Ipamorelin

Primary target

GLP-1 receptor (class B GPCR)Koole 2015

Ghrelin receptor (GHS-R1a) on anterior pituitaryRaun 1998

Pathway

GLP-1R activation → cAMP production → PKA signaling → insulin secretion (pancreatic β-cells)Lu 2025 Koole 2015

GHS-R1a binding → Gαq/11 → ↑intracellular Ca²⁺ → GH vesicle exocytosisRaun 1998 Bowers 1991

Downstream effect

Glucose-dependent insulin release, glucagon suppression, delayed gastric emptying, reduced food intakeLu 2025 Ding 2017

GH pulse amplification, IGF-1 elevation, recovery and lipolytic effectsBowers 2002

Feedback intact?

Yes — physiological secretion and degradation preserved

Yes — pulsatile pattern preserved; somatostatin feedback activeBowers 2002

Origin

Endogenous peptide cleaved from proglucagon in intestinal L cells; secreted postprandially

Pentapeptide H-Aib-His-D-2-Nal-D-Phe-Lys-NH₂; rationally designed for ghrelin-receptor selectivityRaun 1998

Antibody development

—

Not reported in short-term studies

02Dosage Protocols

Parameter

GLP-1 (7-37)

Ipamorelin

Clinical use

None — native GLP-1 not used therapeutically

Engineered analogues (semaglutide, liraglutide) used clinically.Friedman 2024

—

Research dosing

Variable — 0.1–10 nmol/kg in animal models

Used as reference standard for analogue comparison.

—

Half-life

~2 minutes (plasma)Alavi 2021 Ding 2017

Requires continuous infusion for sustained effect.

~2 hoursRaun 1998

Longer than GHRP-6 (15 min); shorter than CJC-1295-DAC (~8 days).

Modified analogues

t½ extended to 13 h (liraglutide), 165 h (semaglutide)

Via DPP-4 resistance + fatty acid acylation.

—

Standard dose

—

200–300 mcg per injectionRaun 1998

Anecdotal community range; clinical doses 1–3 mg IV in trials.

Frequency

—

1–3× per day

Once daily pre-sleep is most common; twice or thrice for advanced users.

Lower / starter dose

—

100 mcg per dose

Evidence basis

—

Phase 1 + clinical practiceRaun 1998 Sigalos 2018

Duration

—

8–12 weeks on / 4 weeks off (anecdotal)

GHS-R desensitisation reported with continuous dosing.

Reconstitution

—

Bacteriostatic water; typical 2 mL per 5 mg vial

Timing

—

Pre-sleep + fasted preferred; 30 min away from food

03Metabolic / Fat Loss Evidence

Parameter

GLP-1 (7-37)

Ipamorelin

Mechanism

GLP-1R activation in hypothalamic satiety centers (arcuate nucleus) reduces food intakeLu 2025

Effect demonstrated with long-acting analogues (liraglutide).Lu 2025

—

Native GLP-1 efficacy

Minimal — rapid degradation prevents sustained appetite suppression

—

Gastric emptying

Delayed in animal models, contributing to satiety

—

Body weight impact

Not observed with native GLP-1 — requires analogue formulations

—

04Side Effects & Safety

Parameter

GLP-1 (7-37)

Ipamorelin

Native GLP-1

Well-tolerated in research settings; no prolonged exposure data

—

Hypoglycemia risk

Low — insulin secretion is glucose-dependent

—

Analogue side effects

Nausea, vomiting, diarrhea (GLP-1R agonists)

Not applicable to native GLP-1 due to non-therapeutic use.

—

GLP-1 resistance

High glucose-induced PKCβ overexpression may reduce GLP-1 responsiveness in endothelial cellsPujadas 2016

—

Cortisol elevation

—

Negligible vs other GHRPsRaun 1998

Prolactin elevation

—

NegligibleRaun 1998

Hunger

—

Mild appetite increase via ghrelin-receptor crosstalk

Injection site reaction

—

Mild irritation possible

GH excess (overdose)

—

Joint pain, edema, insulin resistance

IGF-1 elevation

—

Dose-dependent; monitor with chronic high-dose use

Cancer risk

—

Theoretical via GH/IGF-1 axis; contraindicated in active malignancy

Pregnancy / OB

—

Avoid

Absolute Contraindications

GLP-1 (7-37)

—

Ipamorelin

·Active malignancy or cancer history
·Pregnancy / breastfeeding
·Disrupted hypothalamic-pituitary axis

Relative Contraindications

GLP-1 (7-37)

—

Ipamorelin

·Untreated diabetes
·Severe insulin resistance
·Concurrent corticosteroid use (theoretical desensitisation)

05Administration Protocol

Parameter

GLP-1 (7-37)

Ipamorelin

1. Research use only

Native GLP-1(7-37) is not formulated for therapeutic use. Administered IV or SC in experimental protocols to study GLP-1R pharmacology and as reference standard for analogue development.

Add 2 mL bacteriostatic water to 5 mg vial → 2.5 mg/mL. Roll gently. Solution should be clear.

2. Storage

Lyophilised peptide stored at -20°C or below. Reconstituted solutions should be prepared fresh and used immediately due to rapid degradation.

Subcutaneous, abdomen or thigh. Rotate sites. Pinch fat for shallow SQ delivery.

3. Clinical alternatives

For therapeutic GLP-1R activation, use FDA-approved long-acting analogues: semaglutide (once weekly), liraglutide (once daily), dulaglutide (once weekly), or exenatide (twice daily or once weekly).

Pre-sleep optimal — aligns with natural GH pulse. Some protocols add a morning fasted dose.

4. Storage

—

Lyophilised: room temp, protected from light. Reconstituted: refrigerate 2–8 °C, use within 30 days.

5. Needle

—

29–31G, 4–8 mm insulin syringe.

06Stack Synergy

GLP-1 (7-37)

— no documented stacks

Ipamorelin

+ Tesamorelin

Strong

View Tesamorelin →

Ipamorelin (GHRP) + tesamorelin (GHRH analogue) is the textbook dual-axis GH stack. They activate two distinct pituitary receptors — the ghrelin receptor and the GHRH receptor — producing a synergistic GH pulse larger than either alone. Ipamorelin's selectivity (no cortisol/prolactin spike) makes it the ideal GHRP partner for long-term protocols.

Ipamorelin: 200–300 mcg SQ · pre-sleep
Tesamorelin: 2 mg SQ · same injection · pre-sleep
Primary benefit: Maximal GH pulsatility, fat loss, recovery, sleep depth

Raun 1998 Bowers 2002

+ CJC-1295 (no DAC)

Strong

View CJC-1295 (no DAC) →

CJC-1295 (no DAC) is a short-acting GHRH analogue. Combined with ipamorelin (GHRP), the pulse is amplified across both receptor systems with timing similar to native physiology. Without the DAC modification, the stack maintains sharp peaks rather than the sustained elevation seen with CJC-1295-DAC + ipamorelin.

Ipamorelin: 200–300 mcg SQ · pre-sleep
CJC-1295 (no DAC): 100 mcg SQ · same injection
Primary benefit: Pulsatile GH stimulation matching physiological pattern

Teichman 2006 Ionescu 2006