Source comparison
MK-677 vs Other Growth Hormone Secretagogues: Handling Comparison
MK-677 (Ibutamoren) −20°C (18–24 months) 2–8°C (28 days max) Moderate. Degradation accelerates after 28 days High. Denaturation above 8°C Non-peptide structure offers slightly better stability than true peptides, but cold-chain requirements identical once reco
This comparison does not assign a generated winner or score.
- MK-677 (Ibutamoren)
- −20°C (18–24 months)
- 2–8°C (28 days max)
- Moderate. Degradation accelerates after 28 days
- High. Denaturation above 8°C
- Non-peptide structure offers slightly better stability than true peptides, but cold-chain requirements identical once reconstituted. Longest post-mix window of common secretagogues.
- CJC-1295 (DAC)
- −20°C (24 months)
- 2–8°C (21 days max)
- Short. Begins losing potency after 3 weeks
- Very High. Sensitive to light and heat
- The DAC (Drug Affinity Complex) modification extends in-vivo half-life but makes the compound more fragile in storage. Requires opaque vials.
- Ipamorelin
- −20°C (18 months)
- 2–8°C (14 days max)
- Very Short. Rapid degradation post-reconstitution
- Very High. Highly temperature-sensitive
- Shortest viable storage window of common GH secretagogues. Reconstitute only the amount needed for 2-week protocols. Frequent temperature checks essential.
- GHRP-2
- Short. Potency decline noticeable after 3 weeks
- High. Sensitive to freeze-thaw cycles
- Structurally similar to Ipamorelin but slightly more stable post-mix. Still requires strict refrigeration and limited freeze-thaw exposure.
- MK-677 (ibutamoren) is technically a non-peptide growth hormone secretagogue. It's a small-molecule ghrelin receptor agonist rather than a peptide chain. This structural difference makes it marginally more stable than true peptides like CJC-1295 or Ipamorelin, but the practical handling requirements remain identical: freeze before mixing, refrigerate after mixing, discard after 28 days. The advantage of MK-677's structure appears primarily in oral bioavailability (it can be taken orally, unlike true peptides), not in post-reconstitution stability. Researchers handling multiple secretagogues should note: MK-677's 28-day window is the longest in this category, but it's still a hard deadline, not a suggestion.