Peptide Comparison
GHRH (1-29)vsIpamorelin
The shortest synthetic growth hormone-releasing peptide that tells your body to build taller and stronger.
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
GHRH (1-29)
100–300 mcg
Ipamorelin
100–300 mcg
Frequency
GHRH (1-29)
Once daily
Ipamorelin
Multiple times daily
Administration
GHRH (1-29)
Subcutaneous injection
Ipamorelin
Subcutaneous injection
Cycle Length
GHRH (1-29)
8-12 weeks
Ipamorelin
8-12 weeks
Onset Speed
GHRH (1-29)
Moderate (1-2 weeks)
Ipamorelin
Moderate (1-2 weeks)
Evidence Level
GHRH (1-29)
Strong human trials (Phase 3 or FDA approved)
Ipamorelin
Moderate human trials (Phase 1-2)
Efficacy
Benefit
ratings
Growth and Development
Body Composition
Performance and Recovery
GH Selectivity
Recovery Support
Safety Profile
Technical Data
Compound
specifications
GHRH (1-29)
Molecular Formula
C149H246N44O42S
Molecular Weight
3357.9 g/mol
Half-Life
~10-20 minutes
Bioavailability
Subcutaneous: moderate; Intranasal: 3-5%
CAS Number
86168-78-7
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
GHRH (1-29)
Ipamorelin
Applications
Best
suited for
GHRH (1-29)
Helping Kids Catch Up in Height
Children diagnosed with growth hormone deficiency struggle to reach normal heights. GHRH (1-29) works by sending a signal to the pituitary gland that says 'make more growth hormone.' Studies show children getting daily 30 mcg/kg doses at bedtime experienced sustained improvements in height velocity over 12+ months. It's gentle and lets the body do the work naturally.
Testing for Growth Problems
Doctors need a safe, accurate way to figure out if someone has a growth hormone deficiency. Giving a small dose of GHRH (1-29) and measuring the growth hormone response is fast and specific. It's like asking your pituitary gland 'can you produce growth hormone?' and listening to the answer.
Natural Optimization for Adults
Some adults have lower-than-optimal growth hormone levels as they age. GHRH (1-29) stimulates the body's own hormone factories rather than replacing hormones artificially. This approach keeps your body's natural feedback loops working properly.
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
GHRH (1-29)
Common
- Facial flushing
- Injection site discomfort
- Mild dizziness
Uncommon
- Nausea
- Headache
- Local allergic reaction
Serious
- Cardiovascular complications
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
GHRH (1-29)
Evidence Level
Strong human trials (Phase 3 or FDA approved)
FDA Status
FDA approved for this use
Safety Overview
GHRH (1-29) has been studied extensively in both children and adults. It works by mimicking a natural hormone your body already produces, making it relatively gentle. Side effects are typically mild and temporary, mainly limited to facial flushing and minor injection site reactions. Long-term studies show it's well-tolerated when used as directed.
Contraindications
- xActive malignancy or recent cancer diagnosis
- xAcute critical illness or severe infection
- xKnown hypersensitivity to sermorelin or any component
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 GHRH (1-29) if...
- Children with growth hormone deficiency who need to catch up in height
- Adults seeking to optimize natural growth hormone levels
- People being tested for growth hormone deficiency
Choose Ipamorelin if...
- Muscle recovery and growth
- Anti-aging and vitality
- Body composition improvement
- Sleep quality enhancement