Side-by-side · Research reference

HexarelinvsLL-37

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

APhase 1HUMAN-REVIEWED19/45 cited

BHuman-MechanisticHUMAN-REVIEWED15/35 cited

Hexarelin

Hexapeptide GHRP · Cardio-tropic

100–200 mcgPer doseSmith 1996

Phase 1Evidence levelGhigo 1997

~70 minHalf-lifeSemenistaya 2010

SQ · Multiple sites · 1–3×/day

LL-37

Cathelicidin · Human AMP

Broad-spectrumAntimicrobial activity

Membrane disruptionPrimary mechanismLu 2026 He 2026

Innate immunityHost defense rolePinheiro 2026 Zhang 2026

Endogenous · Secreted at inflammation sites

01Mechanism of Action

Parameter

Hexarelin

LL-37

Primary target

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

Bacterial membranes · Phosphatidylserine-exposed cellsHe 2026 Lu 2026

Pathway

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

hCAP-18 precursor → Proteinase-3 cleavage → LL-37 release → Membrane insertion/disruption

Downstream effect

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

Membrane permeabilization, cytokine induction, autophagy, phagosome-lysosome fusion, chemotaxisAhmad 2026 Zhang 2026

Feedback intact?

Yes initially; tachyphylaxis with chronic useGhigo 1997

—

Origin

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

Endogenous human cathelicidin (37-AA fragment, residues 134–170 of hCAP-18)

Antibody development

—

02Dosage Protocols

Parameter

Hexarelin

LL-37

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

In vitro, animal models, human observational

Duration

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

—

Reconstitution

Bacteriostatic water

—

Timing

Pre-sleep + fasted preferred

—

Half-life

~70 minSemenistaya 2010

—

Endogenous expression

—

Constitutive in neutrophils, epithelial tissues

Upregulated during infection and inflammation.Pinheiro 2026

Exogenous (experimental)

—

Dose varies by study; antimalarial ~10–50 μM in vitro

No FDA-approved exogenous formulation.

Plasma levels (malaria)

—

Elevated in infected patients and miceHe 2026

Exogenous administration reduced parasitemia in murine models.He 2026

04Side Effects & Safety

Parameter

Hexarelin

LL-37

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

—

Cytotoxicity (high dose)

—

Membrane disruption in host cells at supraphysiological concentrations

Pro-inflammatory signaling

—

Can exacerbate inflammation in certain contexts (context-dependent)Pinheiro 2026

Biofilm formation risk

—

LL-37-DNA complexes may stabilize dental plaque biofilmsTanabe 2026

Theoretical cancer risk

—

Immunomodulatory roles in tumor microenvironment under investigation

Absolute Contraindications

Hexarelin

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

LL-37

—

Relative Contraindications

Hexarelin

·Untreated diabetes
·Severe hyperprolactinemia

LL-37

·Active autoimmune disease (theoretical immune dysregulation)

05Administration Protocol

Parameter

Hexarelin

LL-37

1. Reconstitution

Add 2 mL bacteriostatic water to 5 mg vial → 2.5 mg/mL = 250 mcg per 0.1 mL.

LL-37 is constitutively expressed in neutrophils and epithelial cells, cleaved from hCAP-18 by proteinase-3 at sites of infection or inflammation.

2. Injection site

SQ — abdomen or thigh. Rotate sites.

Synthetic LL-37 and derivatives (e.g., SAMP-12aa) tested in vitro and animal models. Administered via topical, intraperitoneal, or intravenous routes in research settings.

3. Timing

Pre-sleep + fasted preferred. Cycle on/off to avoid tachyphylaxis.

LL-37 is resistant to pepsin degradation at gastric pH. Synthetic short peptides designed to retain this stability while reducing toxicity.Lu 2026

4. Storage

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

—

5. Needle

29–31G, 4–8 mm insulin syringe.

—

06Stack Synergy

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

LL-37

— no documented stacks