Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.
| CJC-1295 (without DAC / Mod GRF 1-29) | GHK (without copper) | |
|---|---|---|
| Category | Peptides | Peptides |
| Standard Dose | Research indicates 100-300 mcg administered 1-3 times daily via subcutaneous injection. | Research indicates 1-3% concentration in topical formulations. Injectable dosing follows GHK-Cu protocols at 1-2 mg daily. |
| Timing | Best administered at bedtime (primary), upon waking, and/or post-workout. Always on empty stomach — wait 2+ hours after last meal. Avoid carbohydrates 30+ minutes after injection. | Topical application morning and evening. Injectable in evening. |
| Cycle Duration | 12-24 week cycles with 4-8 week breaks. | Topical use can be ongoing indefinitely. Injectable cycles 8-12 weeks. |
| Evidence Level | moderate_human | moderate_human |
Mod GRF 1-29 (Modified Growth Hormone Releasing Factor, amino acids 1-29) is a truncated and modified GHRH analog that binds to GHRH receptors on anterior pituitary somatotrophs, activating cAMP via Gs protein/adenylate cyclase and mitogen-activated protein kinase pathways. Without the DAC moiety, it has a short half-life of approximately 30 minutes, producing acute GH pulses that more closely mimic natural pulsatile GH secretion. It also stimulates pituitary gene transcription of GH mRNA, preserving endogenous pituitary reserve.
Research indicates 100-300 mcg administered 1-3 times daily via subcutaneous injection.
Best administered at bedtime (primary), upon waking, and/or post-workout. Always on empty stomach — wait 2+ hours after last meal. Avoid carbohydrates 30+ minutes after injection.
12-24 week cycles with 4-8 week breaks.
GHK (glycyl-L-histidyl-L-lysine) is a naturally occurring tripeptide found in human plasma, saliva, and urine that has an extremely high affinity for copper(II) ions. Even without exogenously complexed copper, GHK rapidly chelates available copper in biological systems, making copper-free GHK functionally similar to GHK-Cu in vivo. The peptide stimulates collagen and glycosaminoglycan synthesis, modulates metalloproteinase activity, resets gene expression patterns toward a healthier state (affecting 31.2% of human genes), and activates wound healing cascades.
Research indicates 1-3% concentration in topical formulations. Injectable dosing follows GHK-Cu protocols at 1-2 mg daily.
Topical application morning and evening. Injectable in evening.
Topical use can be ongoing indefinitely. Injectable cycles 8-12 weeks.
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