Side-by-side · Research reference

GLP-1 (7-37)vsHexarelin

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-REVIEWED19/45 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

Hexarelin

Hexapeptide GHRP · Cardio-tropic

100–200 mcgPer doseSmith 1996

Phase 1Evidence levelGhigo 1997

~70 minHalf-lifeSemenistaya 2010

SQ · Multiple sites · 1–3×/day

01Mechanism of Action

Parameter

GLP-1 (7-37)

Hexarelin

Primary target

GLP-1 receptor (class B GPCR)Koole 2015

Ghrelin receptor (GHS-R1a) + cardiac CD36Smith 1996 Ghigo 1997

Pathway

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

GHS-R1a → Gαq → Ca²⁺ → GH release. CD36 engagement → direct cardio-tropic actionGhigo 1997

Downstream effect

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

Strong GH pulse + IGF-1 elevation; cardio-protective effects in animal MI modelsGhigo 1997

Feedback intact?

Yes — physiological secretion and degradation preserved

Yes initially; tachyphylaxis with chronic useGhigo 1997

Origin

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

Synthetic hexapeptide His-D-2-Methyl-Trp-Ala-Trp-D-Phe-Lys-NH₂Smith 1996

Antibody development

—

02Dosage Protocols

Parameter

GLP-1 (7-37)

Hexarelin

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.

~70 minSemenistaya 2010

Modified analogues

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

Via DPP-4 resistance + fatty acid acylation.

—

Standard dose

—

100–200 mcg per injectionSmith 1996

Frequency

—

1–2× per day max (tachyphylaxis with chronic 3× daily)

Lower / starter dose

—

50 mcg per dose

Evidence basis

—

Phase 1 / Phase 2 trialsSmith 1996 Ghigo 1997

Duration

—

4–8 weeks on / 4–8 weeks off (tachyphylaxis mitigation)

Reconstitution

—

Bacteriostatic water

Timing

—

Pre-sleep + fasted preferred

03Metabolic / Fat Loss Evidence

Parameter

GLP-1 (7-37)

Hexarelin

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)

Hexarelin

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

—

Modest at high dosesGhigo 1997

Prolactin elevation

—

Modest at high dosesGhigo 1997

Hunger

—

Strong appetite increase via ghrelin agonism

Tachyphylaxis

—

Receptor desensitisation with chronic dosingGhigo 1997

Cardiac effects

—

Direct cardio-tropic; potential benefit in MI but unstudied in humansGhigo 1997

IGF-1 elevation

—

Strong; monitor with chronic high-dose use

Cancer risk

—

Contraindicated in active malignancy (GH/IGF-1 axis)

Pregnancy / OB

—

Avoid

Absolute Contraindications

GLP-1 (7-37)

—

Hexarelin

·Active malignancy
·Pregnancy / breastfeeding
·Disrupted hypothalamic-pituitary axis

Relative Contraindications

GLP-1 (7-37)

—

Hexarelin

·Untreated diabetes
·Severe hyperprolactinemia

05Administration Protocol

Parameter

GLP-1 (7-37)

Hexarelin

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 = 250 mcg per 0.1 mL.

2. Storage

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

SQ — abdomen or thigh. Rotate sites.

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 + fasted preferred. Cycle on/off to avoid tachyphylaxis.

4. Storage

—

Lyophilised: room temp, light-protected. Reconstituted: refrigerate ≤30 days.

5. Needle

—

29–31G, 4–8 mm insulin syringe.

06Stack Synergy

GLP-1 (7-37)

— no documented stacks

Hexarelin

+ CJC-1295 (no DAC)

Strong

View CJC-1295 (no DAC) →

Hexarelin (GHRP) + CJC-1295-no-DAC (GHRH analogue) is the higher-amplitude variant of the standard GHRH+GHRP stack. Hexarelin produces a stronger pulse than ipamorelin but with cortisol + prolactin signal — choose this stack for maximum GH amplitude when side-effect tolerance is acceptable. Cycle aggressively.

Hexarelin: 100 mcg SQ · pre-sleep
CJC-1295 (no DAC): 100 mcg SQ · same injection
Primary benefit: Maximum GH pulse amplitude (with side-effect signal)

Smith 1996 Teichman 2006