Side-by-side · Research reference

GHRP-2vsGlutathione

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

APhase 2HUMAN-REVIEWED15/42 cited

BHuman-MechanisticHUMAN-REVIEWED6/39 cited

GHRP-2

Hexapeptide GHRP · Phase 2 (clinical diagnostic)

100–300 mcgPer doseBowers 1990

Phase 2Evidence levelBowers 1990 Sigalos 2018

~30 minHalf-lifeMalagón 1999

SQ · Multiple sites · 1–3×/day

Glutathione

Endogenous Tripeptide · Antioxidant

γ-Glu-Cys-GlyStructure

UbiquitousTissue distribution

GCL + GSBiosynthesisWang 2026 Aiana 2026

IV · Oral · Inhaled

01Mechanism of Action

Parameter

GHRP-2

Glutathione

Primary target

Ghrelin receptor (GHS-R1a) on anterior pituitaryBowers 1990

Intracellular redox systems, glutathione peroxidase, glutathione transferase

Pathway

GHS-R1a → Gαq → Ca²⁺ → GH vesicle exocytosisBowers 2002

Synthesized via glutamate-cysteine ligase (GCL) → γ-glutamylcysteine → glutathione synthetase (GS) → GSH

Downstream effect

Strong GH pulse + IGF-1 elevation; appetite increase via ghrelin agonismBowers 2002

Reduction of reactive oxygen species, conjugation of electrophiles, maintenance of cellular thiol-disulfide balance, GPX4 activation for lipid peroxide reduction

Feedback intact?

Yes, with somatostatin feedback active

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Origin

Synthetic hexapeptide; developed by Bowers/Tulane group in the 1980sBowers 1990

Endogenous tripeptide; predominantly synthesized in liver, exported to extracellular space and tissuesTerrell 2025 Hecht 2026

Antibody development

—

02Dosage Protocols

Parameter

GHRP-2

Glutathione

Standard dose

100–300 mcg per injectionBowers 1990

—

Frequency

1–3× per day

—

Lower / starter dose

50 mcg per dose

—

Evidence basis

Phase 2 + clinical diagnostic useBowers 1990

Animal mechanistic + human mechanistic

Duration

8–12 weeks on / 4 off (anecdotal)

—

Reconstitution

Bacteriostatic water

—

Timing

Pre-sleep + fasted preferred

—

Half-life

~30 minMalagón 1999

—

Endogenous synthesis

—

Hepatic synthesis ~10 g/day (basal rate)

Tissue-specific; demand-driven upregulation via Nrf2 signaling.

Exogenous oral

—

250–1000 mg/day

Bioavailability limited; gastric hydrolysis reduces systemic uptake.

IV supplementation

—

600–1200 mg (research protocols)

Used in clinical oxidative stress and hepatic detoxification studies.

Precursor strategy

—

N-acetylcysteine (NAC) 600–1200 mg/day

Provides cysteine for endogenous GSH synthesis; bypasses GI degradation.

04Side Effects & Safety

Parameter

GHRP-2

Glutathione

Cortisol elevation

Mild but measurableBowers 1990

—

Prolactin elevation

Mild but measurable

—

Hunger

Strong appetite increase

—

Injection site reaction

Mild erythema

—

IGF-1 elevation

Strong; monitor with chronic high-dose use

—

Cancer risk

Contraindicated in active malignancy

—

Pregnancy / OB

Avoid

—

Oral supplementation

—

GI discomfort, bloating (mild, dose-dependent)

IV administration

—

Rare hypersensitivity, infusion site reaction

Inhalation

—

Bronchospasm risk in asthma (rare)

Tumor metabolism

—

Extracellular GSH catabolism supplies cysteine to tumors; theoretical concern in active malignancyHecht 2026

Absolute Contraindications

GHRP-2

·Active malignancy
·Pregnancy / breastfeeding

Glutathione

—

Relative Contraindications

GHRP-2

·Untreated diabetes

Glutathione

·Active malignancy (theoretical cysteine supply risk)Hecht 2026
·Severe asthma (inhaled formulations)

05Administration Protocol

Parameter

GHRP-2

Glutathione

1. Reconstitution

Add 2 mL bacteriostatic water to 5 mg vial → 2.5 mg/mL.

Capsule or liquid form, 250–1000 mg once daily. Take on empty stomach for improved absorption, though GI hydrolysis limits bioavailability. NAC precursor strategy often preferred.

2. Injection site

SQ — abdomen or thigh. Rotate sites.

Clinical protocols: 600–1200 mg slow infusion over 30–60 minutes. Used for acute oxidative stress, hepatic detoxification support. Administered in medical settings.

3. Timing

Pre-sleep + fasted preferred.

Nebulized GSH (research protocols). Monitor for bronchospasm in reactive airway patients. Used experimentally for pulmonary oxidative stress.

4. Storage

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

N-acetylcysteine (NAC) 600–1200 mg/day PO. Provides cysteine substrate for endogenous GSH synthesis. Bypasses gastric degradation, preferred for chronic supplementation.

5. Needle

29–31G, 4–8 mm insulin syringe.

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06Stack Synergy

GHRP-2

+ CJC-1295 (no DAC)

Strong

View CJC-1295 (no DAC) →

GHRP-2 + CJC-1295-no-DAC is a higher-amplitude alternative to the ipamorelin + CJC-1295 stack. GHRP-2 produces a stronger pulse but with cortisol + prolactin signal — choose when maximum GH amplitude is the goal and the side-effect tolerance is acceptable.

GHRP-2: 100–200 mcg SQ · pre-sleep
CJC-1295 (no DAC): 100 mcg SQ · same injection
Primary benefit: High-amplitude GH pulse, body composition

Bowers 1990 Teichman 2006

Glutathione

— no documented stacks