Peptide Comparison
Pralmorelin (GHRP-2)vsIpamorelin
A powerful hexapeptide that stimulates growth hormone release—used clinically in Japan for GH testing and studied for healing and anti-inflammatory effects.
A uniquely selective growth hormone booster that tells your pituitary to release more GH without messing with your cortisol or other hormones—making it the 'clean' choice among growth hormone peptides.
At a Glance
Quick
comparison
Dose Range
Pralmorelin (GHRP-2)
100–300 mcg
Ipamorelin
100–300 mcg
Frequency
Pralmorelin (GHRP-2)
Once daily
Ipamorelin
Multiple times daily
Administration
Pralmorelin (GHRP-2)
Subcutaneous injection
Ipamorelin
Subcutaneous injection
Cycle Length
Pralmorelin (GHRP-2)
4-6 weeks
Ipamorelin
8-12 weeks
Onset Speed
Pralmorelin (GHRP-2)
Rapid (hours to days)
Ipamorelin
Moderate (1-2 weeks)
Evidence Level
Pralmorelin (GHRP-2)
Limited human trials
Ipamorelin
Moderate human trials (Phase 1-2)
Efficacy
Benefit
ratings
Muscle & Performance Enhancement
Injury Recovery & Healing
Diagnostic Clinical Use
GH Selectivity
Recovery Support
Safety Profile
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
Ipamorelin
Molecular Formula
C38H49N9O5
Molecular Weight
711.85 g/mol
Half-Life
2 hours
Bioavailability
High when injected subcutaneously
CAS Number
170851-70-4
Protocols
Dosing
tiers
Pralmorelin (GHRP-2)
Ipamorelin
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.
Ipamorelin
Clean GH Boost Seekers
If you want the benefits of increased growth hormone without spiking cortisol or other stress hormones, Ipamorelin is uniquely selective. Unlike GHRP-2 or GHRP-6, it won't raise your cortisol levels even at doses 200 times higher than needed for GH release.
Recovery-Focused Athletes
Ipamorelin shines for athletes who want better recovery between training sessions. The GH boost helps repair muscle tissue faster, and since it doesn't mess with other hormones, you can use it consistently without the rollercoaster effects.
Anti-Aging Enthusiasts
Growth hormone naturally declines as we age, contributing to muscle loss, fat gain, and reduced vitality. Ipamorelin offers a gentle way to restore more youthful GH levels without the risks of actual HGH therapy.
Those Recovering from Steroid Use
Research shows Ipamorelin can help counteract the muscle and bone-weakening effects of glucocorticoid medications. If you've been on steroids for medical reasons, this peptide may help you rebuild what you've lost.
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)
Ipamorelin
Common
- Mild headache
- Injection site reactions
- Water retention
- Increased appetite
Uncommon
- Tingling in hands or feet
- Joint stiffness
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
Ipamorelin
Evidence Level
Moderate human trials (Phase 1-2)
FDA Status
Research compound
Safety Overview
Ipamorelin has shown a favorable safety profile in both animal and human studies. What makes it stand out is its remarkable selectivity—it releases growth hormone without significantly affecting cortisol, ACTH, or other hormones. In clinical trials, it was well-tolerated with mostly mild, temporary side effects. Phase 2 trials in patients recovering from surgery showed no significant safety concerns compared to placebo.
Contraindications
- xActive cancer or history of cancer
- xPregnancy or breastfeeding
- xPituitary disorders or tumors
- xKnown allergy to peptide components
- xChildren and adolescents (growth plates still open)
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 Ipamorelin if...
- Muscle recovery and growth
- Anti-aging and vitality
- Body composition improvement
- Sleep quality enhancement