Peptide Comparison
GHRH (1-29)vsSermorelin
The shortest synthetic growth hormone-releasing peptide that tells your body to build taller and stronger.
The original growth hormone booster that works with your body's natural rhythm—it tells your pituitary gland to release more GH instead of replacing it, keeping your hormonal feedback system healthy and balanced.
At a Glance
Quick
comparison
Dose Range
GHRH (1-29)
100–300 mcg
Sermorelin
100–300 mcg
Frequency
GHRH (1-29)
Once daily
Sermorelin
Once daily
Administration
GHRH (1-29)
Subcutaneous injection
Sermorelin
Subcutaneous injection
Cycle Length
GHRH (1-29)
8-12 weeks
Sermorelin
12+ weeks
Onset Speed
GHRH (1-29)
Moderate (1-2 weeks)
Sermorelin
Moderate (1-2 weeks)
Evidence Level
GHRH (1-29)
Strong human trials (Phase 3 or FDA approved)
Sermorelin
Moderate human trials (Phase 1-2)
Efficacy
Benefit
ratings
Growth and Development
Body Composition
Performance and Recovery
GH Optimization
Sleep Quality
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
Sermorelin
Molecular Formula
C149H246N44O42S
Molecular Weight
3357.9 g/mol
Half-Life
10-20 minutes
Bioavailability
High when injected subcutaneously; degraded orally
CAS Number
86168-78-7
Protocols
Dosing
tiers
GHRH (1-29)
Sermorelin
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.
Sermorelin
Adults Experiencing Age-Related GH Decline
After age 30, your growth hormone production naturally declines about 14% per decade. Sermorelin helps restore more youthful GH levels by stimulating your own pituitary rather than shutting it down with external hormones. It's like giving your hormone system a gentle nudge back to where it used to be.
Body Composition Optimizers
If you're struggling to lose stubborn belly fat or build lean muscle despite diet and exercise, sermorelin can help shift your body composition over time. Studies show it increases lean mass and reduces fat, especially in older adults whose natural GH has declined.
Sleep Quality Seekers
Growth hormone is intimately tied to deep, restorative sleep. By enhancing your natural nighttime GH pulses, sermorelin often improves sleep quality as a welcome side effect. Many users report falling asleep faster and waking more refreshed.
Those Wanting a Safer Alternative to HGH
Direct HGH injections bypass your body's feedback system and can suppress your own production. Sermorelin works differently—it asks your pituitary to make more GH naturally. This preserves your body's regulatory mechanisms and carries a lower risk of side effects.
Safety Profile
Side
effects
GHRH (1-29)
Common
- Facial flushing
- Injection site discomfort
- Mild dizziness
Uncommon
- Nausea
- Headache
- Local allergic reaction
Serious
- Cardiovascular complications
Sermorelin
Common
- Injection site reactions
- Facial flushing
- Headache
- Sleepiness or drowsiness
Uncommon
- Nausea
- Hyperactivity or difficulty sleeping
Serious
- Severe 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
Sermorelin
Evidence Level
Moderate human trials (Phase 1-2)
FDA Status
FDA approved for other use
Safety Overview
Sermorelin has an excellent safety profile backed by FDA approval history and decades of clinical use. Unlike direct HGH, it works through your body's natural feedback mechanisms, which inherently limits excessive hormone levels. Side effects are generally mild and transient—mostly injection site reactions and occasional flushing. The peptide was FDA-approved in 1997 for pediatric use and is one of the most well-studied growth hormone secretagogues available.
Contraindications
- xActive cancer or history of cancer
- xPregnancy or breastfeeding
- xKnown allergy to sermorelin or any peptide components
- xPituitary tumors or other pituitary disorders
- xDiabetic retinopathy
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 Sermorelin if...
- Anti-aging and vitality
- Body composition improvement
- Sleep quality enhancement
- Exercise recovery