Peptide Comparison
Pralmorelin (GHRP-2)vsGHRP-6 (Growth Hormone Releasing Peptide-6)
A powerful hexapeptide that stimulates growth hormone release—used clinically in Japan for GH testing and studied for healing and anti-inflammatory effects.
A synthetic hexapeptide that signals your pituitary to release growth hormone through a unique pathway, with emerging evidence of heart-protective benefits.
At a Glance
Quick
comparison
Dose Range
Pralmorelin (GHRP-2)
100–300 mcg
GHRP-6 (Growth Hormone Releasing Peptide-6)
100–300 mcg
Frequency
Pralmorelin (GHRP-2)
Once daily
GHRP-6 (Growth Hormone Releasing Peptide-6)
Multiple times daily
Administration
Pralmorelin (GHRP-2)
Subcutaneous injection
GHRP-6 (Growth Hormone Releasing Peptide-6)
Subcutaneous injection
Cycle Length
Pralmorelin (GHRP-2)
4-6 weeks
GHRP-6 (Growth Hormone Releasing Peptide-6)
8-12 weeks
Onset Speed
Pralmorelin (GHRP-2)
Rapid (hours to days)
GHRP-6 (Growth Hormone Releasing Peptide-6)
Moderate (1-2 weeks)
Evidence Level
Pralmorelin (GHRP-2)
Limited human trials
GHRP-6 (Growth Hormone Releasing Peptide-6)
Limited human trials
Efficacy
Benefit
ratings
Muscle & Performance Enhancement
Injury Recovery & Healing
Diagnostic Clinical Use
Muscle Recovery and Growth
Cellular Health and Protection
Appetite and Nutrient Intake
Technical Data
Compound
specifications
Pralmorelin (GHRP-2)
Molecular Formula
C45H55N9O6
Molecular Weight
818.0 g/mol
Half-Life
15-60 minutes
Bioavailability
~100% (subcutaneous injection)
CAS Number
158861-67-7
GHRP-6 (Growth Hormone Releasing Peptide-6)
Molecular Formula
C46H56N12O6
Molecular Weight
873.0 g/mol
Half-Life
~2.5 hours
Bioavailability
<1% oral, high subcutaneous
CAS Number
87616-84-0
Protocols
Dosing
tiers
Pralmorelin (GHRP-2)
GHRP-6 (Growth Hormone Releasing Peptide-6)
Applications
Best
suited for
Pralmorelin (GHRP-2)
Athletes and Fitness Enthusiasts
If you're serious about lean muscle gains and recovery, pralmorelin directly stimulates GH release—one of the body's most powerful anabolic hormones. Most athletes in research settings use 100-200 mcg for faster muscle repair and improved performance.
Individuals Recovering from Injury
Recent animal studies show GHRP-2 reduces inflammation and speeds tendon-bone healing. If you're dealing with sports injuries, rotator cuff issues, or fractures, this peptide's anti-inflammatory profile may accelerate recovery when combined with proper rehab.
Those Seeking Diagnostic GH Testing
If your doctor suspects growth hormone deficiency, pralmorelin is the gold-standard diagnostic tool in Japan and many countries. A single injection stimulates GH release, allowing physicians to assess your pituitary function safely and accurately.
Peptide Research Enthusiasts
Pralmorelin is one of the most extensively studied GHRPs worldwide. If you're exploring peptide protocols and understand research-grade products, this is a powerful tool for understanding how your GH axis responds to stimulation.
GHRP-6 (Growth Hormone Releasing Peptide-6)
Athletes and Serious Trainers
If you're hitting the gym hard and want better recovery and muscle growth, GHRP-6 amplifies your body's natural GH response. This is particularly valuable during intense training phases when you want to maximize adaptation and minimize soreness. The appetite stimulation also helps you consume the calories you need to grow.
Those Exploring Novel Peptide Protocols
GHRP-6 offers a unique mechanism through the ghrelin receptor, making it valuable for users who want to explore diverse GH-stimulation pathways. It works distinctly from GHRH-based approaches and pairs well with other GH secretagogues for synergistic effects.
Longevity and Metabolic Health Enthusiasts
Growth hormone plays roles in metabolic health, body composition, and potentially aging markers. GHRP-6's emerging research on cellular protection and antioxidant activation makes it interesting for those interested in broader health optimization beyond just muscle growth.
Safety Profile
Side
effects
Pralmorelin (GHRP-2)
Common
- Facial flushing
- Transient headache
- Increased appetite
- Temporary dizziness or lightheadedness
Uncommon
- Carpal tunnel-like sensations
- Joint or muscle aches
- Sleep quality changes
Serious
- Severe allergic reaction (anaphylaxis)
GHRP-6 (Growth Hormone Releasing Peptide-6)
Common
- Increased Appetite
- Mild Joint or Muscle Discomfort
- Water Retention or Mild Swelling
Uncommon
- Sleep Disturbances
- Mild Dizziness or Lightheadedness
Serious
- Allergic Reaction
Research Status
Safety
& evidence
Pralmorelin (GHRP-2)
Evidence Level
Limited human trials
FDA Status
Research compound
Safety Overview
Pralmorelin (GHRP-2) has been safely used in diagnostic settings in Japan for decades and is well-tolerated in most individuals when used at appropriate doses. The peptide is synthetic and chemically stable, with low immunogenicity risk. However, it is NOT FDA approved and should only be used under medical supervision or within research protocols. Long-term safety data in healthy humans is limited.
Contraindications
- xActive malignancy or unresolved cancer history
- xUncontrolled hypertension or severe cardiovascular disease
- xPregnancy or breastfeeding
- xAcute infection or sepsis
- xUncontrolled diabetes
GHRP-6 (Growth Hormone Releasing Peptide-6)
Evidence Level
Limited human trials
FDA Status
Research compound
Safety Overview
GHRP-6 has a relatively long research history dating back to 1981, with human studies demonstrating its ability to stimulate GH release. The good news is that animal safety studies show excellent tolerability at high doses, and the side effects reported are generally mild and reversible. However, it's not FDA-approved, so use is based on research evidence rather than pharmaceutical oversight. Always purchase from reputable sources and consider medical consultation, especially if you have existing health conditions.
Contraindications
- xKnown allergy or sensitivity to any component of the peptide
- xActive cancer or history of cancer without medical clearance
- xSevere cardiovascular disease or uncontrolled hypertension
- xAcute critical illness or sepsis
Decision Guide
Which is
right for you?
Choose Pralmorelin (GHRP-2) if...
- Athletes seeking enhanced recovery and lean mass gains
- Individuals with suspected GH deficiency (diagnostic use)
- Recovery from tendon or bone injuries
- Those wanting to test GH axis responsiveness
Choose GHRP-6 (Growth Hormone Releasing Peptide-6) if...
- Building lean muscle mass and improving body composition
- Recovery from intense training programs and athletic performance
- Supporting overall metabolic health and longevity markers
- Exploring novel GH-stimulation pathways for those who respond well to peptide protocols