Understand the source comparison
Peptide Half-Life Comparison: Short vs Long-Acting Research Compounds
Short-acting GH secretagogues GHRP-2, Hexarelin 30–90 minutes 2–3× daily Renal filtration, enzymatic degradation Mimics pulsatile endogenous hormone release; requires strict timing but avoids receptor desensitization from constant exposure Long-acting GH secre
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This page preserves a source comparison for education. It does not add a rating, recommendation or clinical judgment.
- Short-acting GH secretagogues
- GHRP-2, Hexarelin
- 30–90 minutes
- 2–3× daily
- Renal filtration, enzymatic degradation
- Mimics pulsatile endogenous hormone release; requires strict timing but avoids receptor desensitization from constant exposure
- Long-acting GH secretagogues
- MK 677
- 24 hours
- Once daily
- Hepatic metabolism
- Sustained receptor activation; preferred for continuous signaling protocols but may suppress endogenous pulsatility
- GLP-1 receptor agonists
- Semaglutide
- ~5 days
- Weekly
- Proteolytic degradation, renal elimination of fragments
- Extended half-life allows weekly dosing; albumin binding prevents rapid clearance; optimal for chronic metabolic studies
- Neuropeptides
- Cerebrolysin
- 90 minutes plasma / 72+ hours biological
- Every 48–72 hours
- Peptidase cleavage, CSF clearance
- Plasma kinetics underestimate biological duration; neurotrophic effects persist long after peptide elimination
- Thymic peptides
- Thymalin
- 2 hours (alpha) / 12 hours (beta)
- Biphasic: rapid distribution then slow tissue release
- Requires loading phase to saturate tissue compartments; multi-dose protocols reach steady state by day 5–7
- Dual receptor agonists
- Mazdutide
- ~160 hours
- Every 7–10 days
- Albumin-mediated protection from proteases
- Extremely long half-life allows infrequent dosing; ideal for compliance-sensitive research models