Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.
| Ipamorelin | TB-500 (Thymosin Beta-4) | |
|---|---|---|
| Category | Peptides | Peptides |
| Standard Dose | Research indicates 200-300 mcg administered 1-3 times daily via subcutaneous injection. | Research indicates 2-2.5 mg administered twice weekly via subcutaneous injection. |
| Timing | Best administered at bedtime for synergy with natural GH peak. Also effective upon waking and post-workout. Always on empty stomach. | No strict timing requirements. Can be administered at any time of day. Systemic action means injection location is not critical. |
| Cycle Duration | 12-24 week cycles with 4-8 week breaks. | Loading phase: 4-6 weeks. Total cycle: 8-16 weeks. |
| Evidence Level | moderate_human | animal_plus_anecdotal |
Ipamorelin is a pentapeptide (Aib-His-D-2-Nal-D-Phe-Lys-NH2) that acts as the first selective growth hormone secretagogue receptor (GHS-R1a/ghrelin receptor) agonist. Unlike other GHRPs, it selectively stimulates GH release without significantly affecting ACTH, cortisol, prolactin, or aldosterone — even at doses 200-fold above the ED50 for GH release. This selectivity profile is comparable to GHRH itself but operates through the distinct ghrelin receptor on pituitary somatotrophs.
Research indicates 200-300 mcg administered 1-3 times daily via subcutaneous injection.
Best administered at bedtime for synergy with natural GH peak. Also effective upon waking and post-workout. Always on empty stomach.
12-24 week cycles with 4-8 week breaks.
TB-500 is a synthetic fragment of Thymosin Beta-4, a 43-amino acid protein that sequesters G-actin monomers, preventing premature polymerization and facilitating cellular migration and morphological changes essential for wound healing. It upregulates actin to promote cell migration, proliferation, and differentiation of stem/progenitor cells at injury sites. TB-500 also enhances angiogenesis, reduces inflammation, and promotes tissue remodeling through increased re-epithelialization and vascular density.
Research indicates 2-2.5 mg administered twice weekly via subcutaneous injection.
No strict timing requirements. Can be administered at any time of day. Systemic action means injection location is not critical.
Loading phase: 4-6 weeks. Total cycle: 8-16 weeks.
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