Hexarelin vs Mod GRF 1-29 vs Sermorelin
A three-way comparison to help you find the right peptide for your research goals.
Hexarelin
Hexarelin is a potent synthetic hexapeptide growth hormone secretagogue. It provides the strongest GH release among GHRPs but is associated with rapid desensitization of receptors.
Full details →Mod GRF 1-29
Mod GRF 1-29 (Modified GRF 1-29, also called CJC-1295 without DAC or Tetrasubstituted GRF 1-29) is a modified growth hormone-releasing hormone analog with improved stability over natural GHRH.
Full details →Sermorelin
Sermorelin is a synthetic analog of GHRH consisting of the first 29 amino acids of the natural hormone. It was previously FDA-approved for GH deficiency diagnosis and treatment in children.
Full details →Side-by-Side Comparison
| Aspect | Hexarelin | Mod GRF 1-29 | Sermorelin |
|---|---|---|---|
| Mechanism | Acts as a ghrelin mimetic with high potency at the GHS receptor. Provides powerful GH release but receptor desensitization occurs faster than with other GHRPs, requiring cycling. | Binds to GHRH receptors in the pituitary gland to stimulate growth hormone release. Four amino acid substitutions improve resistance to enzymatic degradation while maintaining biological activity. | Binds to GHRH receptors in the pituitary gland to stimulate natural GH production and release. Maintains the body's natural feedback mechanisms for GH regulation. |
| Typical Dosage | Typical dosing: 100-200mcg administered 2-3 times daily for 4-6 weeks, followed by an equal off period to allow receptor resensitization. | Typical dosing: 100-300mcg administered 2-3 times daily, usually combined with a GHRP like Ipamorelin for synergistic effects. | Typical dosing: 200-500mcg administered once daily, usually before bed. Some protocols use twice daily dosing. |
| Administration | Subcutaneous injection. Cycling is essential to maintain effectiveness. Often used in short bursts rather than continuous protocols. | Subcutaneous injection. Best administered on empty stomach. Short half-life (~30 minutes) necessitates multiple daily doses, unlike DAC version. | Subcutaneous injection, preferably at bedtime to work with natural GH release patterns. Can be combined with GHRPs for synergistic effects. |
| Side Effects | Water retention, cortisol and prolactin increase, hunger (moderate), tingling, and potential blood pressure effects. | Flushing, headache, dizziness, and injection site reactions. Generally well-tolerated. May cause water retention. | Generally well-tolerated. May cause injection site reactions, headache, flushing, or dizziness. Less side effects than direct GH administration. |
| Best For |
What They Have in Common
Hexarelin, Mod GRF 1-29, Sermorelin are all commonly used for:
Key Differences
Unique to Mod GRF 1-29:
Unique to Sermorelin:
Detailed Analysis
Commonalities
Both Hexarelin and Mod GRF 1-29 are commonly used for Muscle Growth, Recovery & Healing.
Which Should You Choose?
Both peptides have similar evidence levels for their shared goals. Your choice may depend on specific use case, availability, or personal response.
Commonalities
Both Hexarelin and Sermorelin are commonly used for Muscle Growth, Recovery & Healing.
Which Should You Choose?
Hexarelin has stronger evidence for Muscle Growth.
Commonalities
Both Mod GRF 1-29 and Sermorelin are commonly used for Muscle Growth, Fat Loss, Recovery & Healing, Sleep Quality.
Which Should You Choose?
Mod GRF 1-29 has stronger evidence for Muscle Growth.