January 28, 2026 · 14 min read
Growth Hormone Peptides: Tesamorelin vs. Sermorelin vs. CJC-1295
A detailed comparison of the three most popular GHRH analogs — including mechanisms, half-lives, dosing protocols, stacking with Ipamorelin, and research effectiveness.
Growth Hormone
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Introduction: What Are GH Peptides?
Growth hormone (GH) peptides — specifically GHRH analogs — are synthetic peptides that stimulate the pituitary gland to produce and release growth hormone naturally. Unlike exogenous GH injections (which directly introduce synthetic GH into the body), these peptides work with the body's own feedback mechanisms, maintaining a more natural pulsatile secretion pattern.
The three most commonly researched GHRH analogs are Tesamorelin, Sermorelin, and CJC-1295. While they share the same fundamental mechanism — stimulating the GHRH receptor — they differ significantly in structure, half-life, potency, and practical application.
This guide provides a research-focused comparison to help you understand which peptide is most appropriate for a given research context.
Sermorelin (GRF 1-29)
Sermorelin is the simplest of the three — it consists of the first 29 amino acids of naturally occurring GHRH (which has 44 amino acids). It was previously FDA-approved under the brand name Geref for diagnosing and treating growth hormone deficiency in children, though its approval was voluntarily withdrawn in 2008 for commercial reasons, not safety.
Key Characteristics
- Half-life: ~10–20 minutes (very short)
- GH Release Pattern: Sharp, natural pulsatile spikes that closely mimic the body's own GHRH secretion
- Potency: Considered the mildest of the three
- FDA Status: Previously approved; voluntarily withdrawn 2008
- Research Interest: Anti-aging, improved sleep quality, lean body composition
Typical Research Dosing — Sermorelin
100 – 300 mcg · 1×/day · Subcutaneous (before bed)
Typically administered before sleep to synergize with the body's natural nocturnal GH pulse. Cycle: 3–6 months, often with periodic breaks. See the full
Sermorelin guide.
Best for: Researchers looking for the most "natural" GH enhancement with minimal disruption to the body's own feedback loops. Often recommended as a starting point for those new to GH peptide research.
Tesamorelin (Egrifta)
Tesamorelin is a modified GHRH analog — specifically a GHRH(1-44) with a trans-3-hexenoic acid modification that increases its stability and potency compared to native GHRH. It is the only currently FDA-approved GHRH analog, approved under the brand name Egrifta for the reduction of visceral adipose tissue (belly fat) in HIV-associated lipodystrophy.
Key Characteristics
- Half-life: ~26 minutes (moderate)
- GH Release Pattern: Pulsatile, but with a stronger and more sustained GH spike than Sermorelin
- Potency: More potent than Sermorelin; strong clinical evidence
- FDA Status: Currently FDA-approved (Egrifta)
- Research Interest: Visceral fat reduction, body composition, IGF-1 elevation, cognitive function
Typical Research Dosing — Tesamorelin
1 – 2 mg · 1×/day · Subcutaneous
Clinical dosing is 2mg daily (the FDA-approved dose for lipodystrophy). Research protocols often use 1–2mg daily. Cycle: 3–6 months. See the full
Tesamorelin guide.
Best for: Researchers prioritizing visceral fat reduction and body composition improvement, or those who want the most clinically validated GHRH analog with robust published data.
CJC-1295 (with and without DAC)
CJC-1295 exists in two forms that are important to distinguish:
- CJC-1295 DAC — Contains a Drug Affinity Complex (DAC) that binds to albumin in the blood, dramatically extending the half-life to 6–8 days. This provides continuous, sustained GH elevation.
- CJC-1295 no DAC (Modified GRF 1-29 / Mod GRF) — A modified version of Sermorelin with a half-life of ~30 minutes. Produces discrete GH pulses and is commonly stacked with Ipamorelin.
CJC-1295 DAC — Key Characteristics
- Half-life: ~6–8 days (very long)
- GH Release Pattern: Sustained, continuous elevation — not pulsatile
- Potency: Strongest and most sustained IGF-1 elevation
- FDA Status: Not FDA-approved
- Research Interest: Maximum GH/IGF-1 elevation, muscle growth, fat loss
Typical Research Dosing — CJC-1295 DAC
2 mg · 1×/week · Subcutaneous
Dosed once weekly due to the extended half-life. Some protocols use 2mg every 5 days. See the full
CJC-1295 guide.
CJC-1295 no DAC (Mod GRF 1-29) — Key Characteristics
- Half-life: ~30 minutes
- GH Release Pattern: Pulsatile (similar to natural pattern)
- Potency: Stronger than Sermorelin due to amino acid modifications that resist enzymatic breakdown
- Stacking: Most commonly stacked with Ipamorelin for synergistic effect
Typical Research Dosing — CJC-1295 no DAC + Ipamorelin Stack
100 mcg Mod GRF + 100 mcg Ipamorelin · 1–3×/day · Subcutaneous
Administered together, typically before bed and/or upon waking. The GHRH (Mod GRF) and GHRP (Ipamorelin) work synergistically to produce a stronger GH pulse. See the
Ipamorelin guide.
DAC vs No DAC: DAC version is simpler (once weekly) but produces non-physiological continuous GH elevation. No-DAC version requires more frequent dosing but maintains natural pulsatile GH patterns, which some researchers prefer for long-term use.
Head-to-Head Comparison
| Feature | Sermorelin | Tesamorelin | CJC-1295 DAC | Mod GRF (no DAC) |
|---|
| Type | GHRH(1-29) | Modified GHRH(1-44) | GHRH + DAC | Modified GHRH(1-29) |
| Half-Life | 10–20 min | ~26 min | 6–8 days | ~30 min |
| GH Pattern | Pulsatile | Pulsatile | Sustained | Pulsatile |
| Potency | Mild | Moderate–High | High | Moderate |
| Dosing | 100–300 mcg/day | 1–2 mg/day | 2 mg/week | 100 mcg 1–3×/day |
| FDA Status | Withdrawn (2008) | Approved (Egrifta) | Not approved | Not approved |
| Best For | Mild GH boost, sleep, anti-aging | Visceral fat loss, clinical use | Max GH/IGF-1, muscle growth | Ipamorelin stacking |
| Stacking | Can stack with GHRPs | Standalone | Standalone | Best with Ipamorelin |
| Side Effects | Mildest profile | Injection site reactions | Water retention, joint stiffness | Mild; similar to Sermorelin |
Understanding GHRH + GHRP Stacking
To fully understand GH peptide protocols, it helps to know the difference between two categories:
GHRH Analogs (Stimulate GH Release)
These include Sermorelin, Tesamorelin, CJC-1295, and Mod GRF. They bind to the GHRH receptor on the pituitary gland and tell it to produce and release growth hormone. They're the "signal" that initiates the process.
GHRPs (Amplify the Signal)
Growth Hormone Releasing Peptides like Ipamorelin, GHRP-2, and GHRP-6 bind to ghrelin receptors and amplify the GH release signal. They also suppress somatostatin (the hormone that inhibits GH release).
Why stack? Using a GHRH analog and a GHRP together produces a synergistic GH pulse significantly stronger than either alone. Think of GHRH as pressing the gas pedal, and GHRP as releasing the brake — together, you get maximum acceleration.
The most popular stack is Mod GRF 1-29 (CJC-1295 no DAC) + Ipamorelin, because Ipamorelin is the most selective GHRP with minimal side effects (no significant impact on cortisol, prolactin, or appetite — unlike GHRP-2 and GHRP-6).
Which GH Peptide Is Right for Your Research?
Choose Sermorelin if:
- You want the most natural, gentle GH enhancement
- Sleep quality improvement is a primary goal
- You're new to GH peptide research and want to start mild
- Long-term anti-aging protocols are the focus
Choose Tesamorelin if:
- Visceral fat reduction is the primary research target
- You want the most clinically validated option with published human data
- Body composition improvement is the focus
- FDA-approved status is important for your research context
Choose CJC-1295 DAC if:
- Maximum sustained GH/IGF-1 elevation is the goal
- You prefer once-weekly dosing for convenience
- Muscle growth and recovery are primary targets
- You understand the trade-off of non-pulsatile GH release
Choose Mod GRF + Ipamorelin if:
- You want the strongest pulsatile GH release with minimal side effects
- Synergistic stacking for maximum natural-pattern GH secretion
- You're comfortable with 1–3 daily injections
- Clean GH release without cortisol/prolactin elevation matters
Frequently Asked Questions
What's the difference between Tesamorelin, Sermorelin, and CJC-1295? ▼
All three stimulate natural GH production via the GHRH receptor. Sermorelin is the mildest with a 10–20 minute half-life. Tesamorelin is FDA-approved and moderately potent with a 26-minute half-life. CJC-1295 DAC has a 6–8 day half-life for sustained GH elevation. They differ in potency, dosing frequency, and use cases.
Which GH peptide is the most potent? ▼
CJC-1295 DAC produces the most sustained IGF-1 elevation. Tesamorelin has the strongest clinical evidence. For pulsatile GH release, Mod GRF + Ipamorelin stack is considered the most effective combination.
Can you stack CJC-1295 with Ipamorelin? ▼
Yes — specifically CJC-1295 without DAC (Mod GRF 1-29) is commonly stacked with Ipamorelin at 100 mcg each, 1–3 times daily. The GHRH + GHRP combination produces synergistic GH pulses stronger than either alone.
What's the difference between CJC-1295 with DAC and without DAC? ▼
The DAC (Drug Affinity Complex) binds to blood albumin, extending the half-life from ~30 minutes to 6–8 days. DAC version = once weekly dosing with continuous GH. No-DAC version = 1–3× daily dosing with natural pulsatile GH. Most stacking protocols use the no-DAC version.
Is Tesamorelin FDA-approved? ▼
Yes, Tesamorelin (brand name Egrifta) is FDA-approved for visceral fat reduction in HIV-associated lipodystrophy. It's the only currently FDA-approved GHRH analog.
What are the side effects of GH peptides? ▼
Common side effects include water retention, joint stiffness, tingling in extremities, and increased appetite. CJC-1295 DAC may cause more prolonged effects due to its long half-life. Sermorelin has the mildest side effect profile. Prolonged GH peptide use can theoretically increase insulin resistance.
Calculate Your Exact GH Peptide Dose
Use our free dosing calculator for Tesamorelin, Sermorelin, CJC-1295, or any peptide reconstitution.
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