MK-677 vs Bremelanotide
Head-to-head comparison of MK-677 (Ibutamoren Mesylate (MK-677)) and Bremelanotide (Bremelanotide (PT-141), cyclic melanocortin receptor agonist) — benefits, dosing, side effects, research data, and where to buy.
Research Score
| Property | MK-677 | Bremelanotide |
|---|---|---|
| Category | Growth Hormone | Sexual Health |
| Full Name | Ibutamoren Mesylate (MK-677) | Bremelanotide (PT-141), cyclic melanocortin receptor agonist |
| Molecular Weight | 528.662 g/mol | 1025.2 Da |
| Half-Life | ~24 hours | about 2.7 h |
| Amino Acids | Non-peptide compound | 7 |
| Typical Dose | — | 1.75 mg |
| Route | — | Subcutaneous |
| Purity | >99% | ≥98% |
| Studies Count | 120 | 200 |
| Research Status | Active Research | Clinical |
MK-677 Benefits
- ✓Oral GH secretagogue, 24-hour GH elevation, increases IGF-1, improves sleep quality, increases lean mass, does not suppress natural GH
Bremelanotide Benefits
- ✓increases sexual desire
- ✓supports arousal
- ✓may improve erectile response
- ✓on-demand use
MK-677 Dosing
10-25 mg orally once daily before bedtime. 25 mg is the most studied dose. Can be used long-term without cycling.
Bremelanotide Dosing
1.75 mg subcutaneous PRN|administer about 45 minutes before activity|max 1 dose per 24 hours
MK-677 Side Effects
- ⚠Increased appetite, mild water retention, drowsiness, transient numbness, mild increase in fasting blood glucose with long-term use.
Bremelanotide Side Effects
- ⚠nausea
- ⚠flushing
- ⚠headache
- ⚠transient blood pressure increase
Research Overview
MK-677
A landmark 2-year study in elderly adults demonstrated significant increases in lean mass, GH pulsatility, and IGF-1 to youthful ranges. Selectively agonizes GHS-R1a without increasing cortisol or prolactin.
Bremelanotide
Human studies and approval data support meaningful effects on sexual desire in women, with a central mechanism involving melanocortin signaling. It is one of the most clinically relevant peptides in this category and is commonly used as the reference compound for PT-141-type research.
Ready to buy?
Find both peptides from our verified, lab-tested vendors with purity certificates and third-party testing.