Mod GRF 1-29 vs Tirzepatide
A detailed comparison to help you understand the differences and choose the right peptide for your research goals.
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 →Tirzepatide
Tirzepatide is a first-in-class dual GIP/GLP-1 receptor agonist. FDA-approved as Mounjaro (diabetes) and Zepbound (weight loss), it has shown superior weight loss results compared to semaglutide in clinical trials.
Full details →Side-by-Side Comparison
| Aspect | Mod GRF 1-29 | Tirzepatide |
|---|---|---|
| Mechanism | 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. | Activates both GIP (glucose-dependent insulinotropic polypeptide) and GLP-1 receptors, providing synergistic effects on insulin secretion, appetite suppression, and metabolic regulation. The dual mechanism may explain its enhanced efficacy. |
| Typical Dosage | Typical dosing: 100-300mcg administered 2-3 times daily, usually combined with a GHRP like Ipamorelin for synergistic effects. | Start at 2.5mg weekly, titrate every 4 weeks through 5mg, 7.5mg, 10mg, 12.5mg, to maximum 15mg weekly. Full titration takes approximately 20 weeks. |
| Administration | Subcutaneous injection. Best administered on empty stomach. Short half-life (~30 minutes) necessitates multiple daily doses, unlike DAC version. | Subcutaneous injection once weekly. Rotate injection sites. Slower titration may help reduce GI side effects. |
| Side Effects | Flushing, headache, dizziness, and injection site reactions. Generally well-tolerated. May cause water retention. | Similar to semaglutide: nausea, diarrhea, vomiting, constipation, abdominal pain, decreased appetite. Generally improve with continued use. |
| Best For |
What They Have in Common
Both Mod GRF 1-29 and Tirzepatide are commonly used for: