GHRP-2 vs Retatrutide
Well Studied vs Extensively Studied
monitor Mechanism-based · 47% Both GHRP-2 and Retatrutide affect insulin sensitivity or blood glucose. Monitor fasting glucose and HbA1c. Consider adding an insulin sensitizer (metformin/berberine).
Molecular Data
GHRP-2 Retatrutide
Weight 817.9 Da 4,731.33 Da
Half-life ~30 minutes ~6 days
Chain 6 amino acids 39 amino acids
Type Synthetic hexapeptide Triple GLP-1/GIP/glucagon agonist
Key Benefits
GHRP-2
01 Potent stimulation of natural growth hormone release
02 Enhanced muscle growth and recovery
03 Improved body composition and fat metabolism
04 Better sleep quality and recovery
05 Increased appetite (can be beneficial for bulking)
06 Maintains natural GH pulsatile release patterns
07 Synergistic effects when combined with GHRH peptides
Retatrutide
01 Superior weight loss (24.2% at 48 weeks)
02 Improved glycemic control (HbA1c reduction up to 2.16%)
03 Enhanced cardiovascular benefits
04 Hepatic fat reduction (up to 82%)
05 Triple mechanism addresses obesity through multiple pathways
Dosing Protocols
GHRP-2
100-300 mcg / 2-3x daily
GH optimization 100-150 mcg 2-3x daily
Enhanced results 200-300 mcg 2-3x daily
With GHRH (synergy) 100 mcg each 2-3x daily
Pre-sleep protocol 100-200 mcg Before bed
Retatrutide
0.5mg starting, titrate up to 8-12mg weekly / Once weekly (same day each week)
Starting Dose (Week 1-4) 0.5mg Once weekly
Low Maintenance (Week 4-8) 1mg Once weekly
Escalation (Week 8-12) 2mg Once weekly
Moderate (Week 12-16) 4mg Once weekly
Advanced (Week 16-20) 8mg Once weekly
Maximum Efficacy (Week 20+) 12mg Once weekly
Side Effects
GHRP-2
Increased appetite (less than GHRP-6)
Mild water retention
Tingling or numbness in extremities
Tiredness or lethargy after injection
Mild headache
Retatrutide
Gastrointestinal effects (nausea, vomiting, diarrhea)—typically mild to moderate
Heart rate increases—common especially in first 24 weeks
Appetite suppression
Mild dehydration
Contraindications
Active cancer or history of cancer
Pregnancy or breastfeeding
Pituitary disorders
Diabetic retinopathy
WADA prohibited for competitive athletes
Personal or family history of medullary thyroid carcinoma
MEN2 syndrome
Severe renal impairment
Research Evidence
GHRP-2 Retatrutide
Status Well Studied Extensively Studied
References 3 studies 6 studies
Latest — 2025-10
FDA Approved No No
This comparison is for educational and research purposes only. Consult a healthcare professional before use.