GHRP-6 vs IGF-1 LR3 vs Mod GRF 1-29
A three-way comparison to help you find the right peptide for your research goals.
GHRP-6
Growth Hormone Releasing Peptide 6 (GHRP-6) is one of the first synthetic growth hormone secretagogues discovered. It stimulates significant GH release but is known for causing intense hunger.
Full details →IGF-1 LR3
IGF-1 LR3 (Long R3 Insulin-like Growth Factor-1) is a modified version of IGF-1 with extended half-life and enhanced potency. The modifications prevent binding to IGF binding proteins, increasing bioavailability.
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 →Side-by-Side Comparison
| Aspect | GHRP-6 | IGF-1 LR3 | Mod GRF 1-29 |
|---|---|---|---|
| Mechanism | Acts as a ghrelin mimetic, binding to the GHS-R receptor in the pituitary and hypothalamus. Stimulates GH release and also significantly increases appetite by mimicking ghrelin's hunger-signaling effects. | Binds to IGF-1 receptors to promote protein synthesis, muscle growth, and fat metabolism. The LR3 modification (13 amino acid extension and arginine substitution) extends half-life from minutes to 20-30 hours. | 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. |
| Typical Dosage | Typical dosing: 100-300mcg administered 2-3 times daily. Often combined with GHRH peptides like CJC-1295 for synergistic effects. | Research protocols typically use 20-100mcg daily, often divided into multiple injections or administered bilaterally to target muscles. | Typical dosing: 100-300mcg administered 2-3 times daily, usually combined with a GHRP like Ipamorelin for synergistic effects. |
| Administration | Subcutaneous injection. Best administered on an empty stomach. The strong hunger response can be beneficial for those trying to gain weight but challenging for cutting. | Intramuscular injection (site-specific growth) or subcutaneous for systemic effects. Often cycled 4-6 weeks on, equal time off. | Subcutaneous injection. Best administered on empty stomach. Short half-life (~30 minutes) necessitates multiple daily doses, unlike DAC version. |
| Side Effects | Intense hunger (most notable effect), water retention, increased cortisol and prolactin, tingling/numbness, and potential blood pressure changes. | Hypoglycemia, joint pain, water retention, potential jaw/hand growth with extended use, and injection site reactions. | Flushing, headache, dizziness, and injection site reactions. Generally well-tolerated. May cause water retention. |
| Best For |
What They Have in Common
GHRP-6, IGF-1 LR3, Mod GRF 1-29 are all commonly used for:
Key Differences
Unique to IGF-1 LR3:
Unique to Mod GRF 1-29:
Detailed Analysis
Commonalities
Both GHRP-6 and IGF-1 LR3 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 GHRP-6 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 IGF-1 LR3 and Mod GRF 1-29 are commonly used for Muscle Growth, Fat Loss, 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.