CJC-1295 with DAC vs GHRH (1-29)
Long-acting growth hormone releaser that works around the clock to boost your body's natural GH production with just one or two injections per week.
The 29-amino-acid fragment of growth hormone-releasing hormone, and the shortest piece of it with full activity. Approved in 1997 as Geref for growth failure in children with growth hormone deficiency and discontinued in 2008; the one controlled trial in older adults tested a modified version of the molecule, not this one [1][5][7].
Written by Michael Carroll — Owner, Director of Research · Reviewed by the Peptide Initiative Research Team · Editorial standards
Quick comparison
Dose range
CJC-1295 with DAC
2–2 mg
GHRH (1-29)
30–30 mcg/kg/day
Frequency
CJC-1295 with DAC
Twice weekly
GHRH (1-29)
Once daily at bedtime
Administration
CJC-1295 with DAC
Subcutaneous injection
GHRH (1-29)
Subcutaneous injection
Cycle length
CJC-1295 with DAC
8-12 weeks
GHRH (1-29)
Continuous — the label treats until the growth plates fuse
Onset speed
CJC-1295 with DAC
Moderate (1-2 weeks)
GHRH (1-29)
Height velocity measurable at 6 months in children; nothing established in adults
Evidence level
CJC-1295 with DAC
Moderate human trials (Phase 1-2)
GHRH (1-29)
Human trials in children; one 19-person adult trial of a modified analogue
Benefit ratings
GH Elevation
Convenience
Recovery Support
Growth and Development
Body Composition
Performance and Recovery
Compound specifications
CJC-1295 with DAC
Molecular formula
C165H269N47O46
Molecular weight
3647.28 g/mol
Half-life
6-8 days
Bioavailability
~100% (subcutaneous)
CAS number
863288-34-0
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
Dosing compared
CJC-1295 with DAC
Subcutaneous
1 mg (1000 mcg)
Once weekly · 2-4 weeks
A starting dose used in practice. The DAC version is long-acting (about a 6-8 day half-life), so weekly dosing keeps growth hormone and IGF-1 raised. In the Phase 1 trial a single dose raised GH for 6+ days and IGF-1 for up to 11 days. [2]
2 mg (2000 mcg)
Once weekly (or split twice weekly) · 8-12 weeks
The common maintenance dose, roughly in line with the 30-60 mcg/kg weekly range studied in the Phase 1 trial. [1][2] In the ascending-dose trials, single injections raised mean GH 2- to 10-fold for six or more days and IGF-I 1.5- to 3-fold for 9-11 days; 30 and 60 µg/kg doses were the best tolerated [2].
2 mg per dose
Twice weekly · 8-12 weeks
A higher total weekly amount split into two doses, used by experienced users; near the top of the 30-60 mcg/kg weekly range from the clinical study. [2]
GHRH (1-29)
Subcutaneous
30 mcg/kg/day
Once daily at bedtime · Continuous — trials ran 12 months; the label treats until the growth plates fuse
The approved Geref dose and the only dose of this molecule tested once daily: 30 mcg/kg (0.03 mg/kg) subcutaneously at bedtime in prepubertal children with growth hormone deficiency. In the 110-child pivotal trial it raised height velocity from 4.1 to 8.0 cm/year at 6 months [5]. The same 30 mcg/kg total has also been given as 15 mcg/kg TWICE daily in children with radiation-induced deficiency [6]. Two things this dose is not: it is not an adult dose — no trial has given sermorelin at 30 mcg/kg to adults, and for a 75 kg adult it would be 2,250 mcg — and it is not equivalent to growth hormone, which produced larger height gains at the same microgram-per-kilogram dose [1].
10 mcg/kg/day
Once nightly · 16 weeks in the only controlled adult trial
Read the molecule before you read the number. The only controlled trial in older adults used [Nle27]GHRH-(1-29)-NH2 — a norleucine-27 analogue, not sermorelin — at 10 mcg/kg nightly for 16 weeks in 19 people aged 55 to 71 [7][8]. That is roughly 750 mcg for a 75 kg adult. GH and IGF-I rose, but IGF-I drifted back toward baseline by week 16; lean mass, insulin sensitivity, well-being and libido improved in men only; body fat and bone density did not change in either sex; sleep was unaffected [7]. The fixed 200-300 mcg nightly figure that circulates for adults is community practice — it appears in no trial and on no label, and it is 3 to 4 times below this studied dose. It is listed here because people use it, not because it has evidence behind it.
Best suited for
CJC-1295 with DAC
Growth Hormone Optimization
CJC-1295 with DAC excels at providing a sustained, steady elevation of growth hormone levels. Unlike shorter-acting peptides that create brief spikes, the DAC modification keeps GH elevated for days, mimicking a more youthful hormone profile.
Muscle Building and Recovery
By increasing both GH and IGF-1 levels, this peptide supports protein synthesis and muscle repair. Users often notice improved recovery between workouts and better ability to build and maintain lean muscle mass.
Anti-Aging and Longevity
Growth hormone naturally declines with age, contributing to many signs of aging. CJC-1295 with DAC helps restore more youthful GH levels, potentially supporting better skin quality, energy levels, and overall vitality.
Body Composition Improvement
The combination of increased GH and IGF-1 promotes fat metabolism while preserving muscle tissue. Many users experience gradual fat loss, particularly in stubborn areas, while maintaining or building lean mass.
Convenient Weekly Dosing
Unlike peptides requiring daily or twice-daily injections, the extended half-life of CJC-1295 with DAC means just one or two injections per week provide continuous benefits. Ideal for those who want results without daily protocols.
GHRH (1-29)
Helping Kids Catch Up in Height
Children with growth hormone deficiency grow slowly because the signal to release growth hormone is weak. GHRH(1-29) supplies that signal. In the 110-child trial behind the approval, 30 mcg/kg at bedtime nearly doubled height velocity in the first 6 months, and bone age advanced in step with height rather than racing ahead of it [5]. It is also fair to say that growth hormone itself worked better, which is part of why this product left the market [1].
Testing for Growth Problems
A single intravenous dose of 1 mcg/kg is a rapid and relatively specific test of whether the pituitary can release growth hormone, and it produces fewer false positives in children without deficiency than other provocative tests. A normal response does not rule deficiency out, though — a hypothalamic cause can pass this test, so it is used alongside conventional testing rather than instead of it [1].
Adults — what is actually known
GHRH works upstream: it asks the pituitary to release its own growth hormone rather than replacing the hormone, so the body's feedback loops stay in the circuit. That is a real mechanical difference from injecting growth hormone. What it has not been shown to do is change how adults look or perform. The only controlled adult trial ran 16 weeks in 19 people aged 55-71, used a modified version of the molecule, and found lean mass and well-being improved in men but not women, with no change in body fat [7][8]. No trial has tested sermorelin itself in healthy adults.
Side effects
CJC-1295 with DAC
Common
- Injection site reactions
- Water retention
- Flushing
- Tingling sensation
Uncommon
- Headaches
- Fatigue or lethargy
- Joint discomfort
Serious
- Carpal tunnel symptoms
- Blood glucose elevation
GHRH (1-29)
Common
- Transient facial flushing
- Injection site reaction
Uncommon
- Hypothyroidism
- Anti-GRF antibodies
- Transient raised blood lipids
Serious
- Hypersensitivity reaction
Safety & evidence
CJC-1295 with DAC
Evidence level
Moderate human trials (Phase 1-2)
FDA status
Research compound
Safety overview
CJC-1295 with DAC was evaluated in Phase 1-2 human clinical trials where it demonstrated a generally favorable safety profile. The most common adverse events were mild injection site reactions including temporary pain, swelling, and redness. No serious adverse events were reported in the published clinical studies. The compound was being developed for HIV-associated lipodystrophy before the program was discontinued.
Contraindications
- Active cancer or history of malignancy
- Pregnancy or breastfeeding
- Pituitary tumors or disorders
- Diabetic retinopathy
- Uncontrolled diabetes
GHRH (1-29)
Evidence level
Human trials in children; one 19-person adult trial of a modified analogue
FDA status
Approved 1997 as Geref for growth failure in children with growth hormone deficiency; discontinued by the manufacturer in July 2008 and no longer marketed in the US. FDA determined in 2013 it was not withdrawn for safety or effectiveness reasons. Sermorelin sold today is compounded, not an FDA-approved product.
Safety overview
The largest safety dataset is the 110-child pivotal trial, where 30 mcg/kg/day for up to a year produced no adverse changes in general biochemical or hormonal analyses, no change in fasting glucose, and no excessive IGF-I generation [5]. Across the paediatric programme the most commonly reported adverse events were transient facial flushing and pain at the injection site [1]. The Geref prescribing information puts numbers on that: an injection reaction — pain, swelling or redness — in about 1 patient in 6, with 3 of 350 exposed patients discontinuing because of it; hypothyroidism in 6.5% during therapy, which is why the label requires thyroid testing before and during treatment; and anti-GRF antibodies in a large proportion of patients at least once during treatment, of unclear significance and with no apparent effect on growth. In the 19-adult trial of the norleucine-27 analogue the only adverse effect was transient hyperlipidaemia, which resolved by the end of the study [7], and the companion immune paper reported no adverse effects [8].
Contraindications
- Known hypersensitivity to sermorelin or any excipient
- Closed growth plates, if the goal is height — the label stops treatment once the epiphyses fuse
- Pregnancy and breastfeeding — no human data
Which is right for you?
Choose CJC-1295 with DAC if...
- Boosting natural growth hormone production
- Building lean muscle mass
- Improving body composition
- Anti-aging and longevity
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