MK-677 (Ibutamoren) vs Ipamorelin
Dosing, half-life, mechanism, benefits, and safety — side by side.
MK-677 (Ibutamoren)
ResearchOral growth hormone secretagogue mimicking ghrelin
Half-Life
~24 hours
Route
Oral
Dose
10-25 mg Daily
MW
528.67 Da
Ipamorelin
ResearchSelective growth hormone releasing peptide with minimal side effects
Half-Life
~2 hours
Route
SC
Dose
100-300 mcg 1-3x/day
MW
711.85 Da
Quick Reference
| MK-677 (Ibutamoren) | Ipamorelin | |
|---|---|---|
| Category | N/A | N/A |
| Route | Oral | SC |
| Typical Dose | 10-25 mg Daily | 100-300 mcg 1-3x/day |
| Frequency | Daily | N/A |
| FDA Approved | No | No |
| WADA Status | Banned | Banned |
⏱ Pharmacokinetics
| MK-677 (Ibutamoren) | Ipamorelin | |
|---|---|---|
| Half-Life | ~24 hours | ~2 hours |
| Research Status | Research compound - Growth hormone secretagogue | Research compound - Growth hormone agonist |
| CAS Number | 159634-47-6 | 170851-70-4 |
Molecular
| MK-677 (Ibutamoren) | Ipamorelin | |
|---|---|---|
| Molecular Weight | 528.67 | 711.85 |
| Molecular Formula | C28H40N4O5S | C38H49N9O5 |
| Sequence Length | N/A | 28 aa |
| Mechanism | Oral ghrelin mimetic and GH secretagogue | Selective GH secretagogue with minimal side effects |
Key Benefits
| MK-677 (Ibutamoren) | Ipamorelin | |
|---|---|---|
| Benefits | Muscle growth; Improved sleep quality; Bone density; Growth hormone elevation; Enhanced recovery; Increased appetite; Catabolism Reversal: Nitrogen balance +0.31 vs -1.48 g/day; Fat-Free Mass: Significant increase in obese subjects | Increases lean muscle mass; Reduces body fat; Improves sleep; Collagen production.; Muscle protein synthesis; Improved sleep quality; Collagen turnover support; Clean GH stimulation |
Safety & Warnings
| MK-677 (Ibutamoren) | Ipamorelin | |
|---|---|---|
| Safety Note | Research compound only. Not approved for human use. | Research compound only. Forbidden in sport. May cause temporary flushing, mild head pressure, or minor water retention. |
| Side Effects | Glucose elevation; Insulin resistance; Transient edema; Lethargy; Water retention; Elevated blood sugar; Mild side effect; Mild-Moderate side effect | Does NOT stimulate ACTH or cortisol (unique selectivity profile); No ACTH/cortisol release; Injection site reactions; Overall AE incidence; Mild dizziness; Rare local irritation; Headache; Mild side effect |
| Athlete Warning | 🛑 WADA BANNED - Prohibited in competitive sports as growth hormone secretagogue | 🛑 WADA BANNED - Prohibited in competitive sports as selective growth hormone releasing peptide |
Which should you choose?
MK-677 (Ibutamoren) has a longer half-life (~~24 hours) than Ipamorelin (~~2 hours), which can mean less frequent dosing.
MK-677 (Ibutamoren) vs Ipamorelin — FAQ
Which has a longer half-life: MK-677 (Ibutamoren) or Ipamorelin?
MK-677 (Ibutamoren) has a half-life of ~~24 hours while Ipamorelin has a half-life of ~~2 hours. A longer half-life generally means less frequent dosing and more stable levels.
Can I stack MK-677 (Ibutamoren) and Ipamorelin together?
Whether MK-677 (Ibutamoren) and Ipamorelin can be stacked depends on their mechanisms and receptor targets. Use the stack compatibility checker to analyze synergies and conflicts before combining any peptides.
Which is better: MK-677 (Ibutamoren) or Ipamorelin?
There is no universal "better" peptide — it depends on your goal. MK-677 (Ibutamoren) is Oral ghrelin mimetic and GH secretagogue. Ipamorelin is Selective GH secretagogue with minimal side effects. Choose based on your primary goal and research profile.
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