What is the difference between MK-677 and Hexarelin?

MK-677 (Ibutamoren (MK-677)) is graded B+ and is Not FDA-approved — investigational (orally active GH secretagogue). Hexarelin (Hexarelin (HEX)) is graded B and is Not FDA-approved — research compound (cardioprotective signals investigated). They are commonly compared because they share the categories: growth-hormone.

Which has stronger clinical evidence — MK-677 or Hexarelin?

On our internal evidence scale, MK-677 is B+ and Hexarelin is B. A+ indicates large RCTs plus FDA approval; C indicates primarily preclinical or anecdotal evidence.

What is the typical dose of MK-677 vs Hexarelin?

MK-677: 10–25 mg orally, once daily. Hexarelin: 100 mcg, 1–2 times daily (subcutaneous). Always work with a licensed clinician — peptide dosing should be individualized.

MK-677 vs Hexarelin

Both MK-677 and Hexarelin are used for growth-hormone. Here's how their evidence, dosing, and regulatory status actually compare.

MK-677

Evidence B+

Ibutamoren (MK-677)

An orally active ghrelin-receptor agonist that drives 24-hour increases in GH and IGF-1. Technically a non-peptide small molecule but always grouped with GH peptides.

View full MK-677 profile →

Hexarelin

Evidence B

Hexarelin (HEX)

The strongest GH-releasing hexapeptide and one of the few peptides with documented direct cardiac benefits in animal models. Tachyphylaxis (diminished response over time) limits long-term use.

View full Hexarelin profile →

Side-by-Side

Attribute	MK-677	Hexarelin
Evidence Grade	B+	B
FDA Status	Not FDA-approved — investigational (orally active GH secretagogue)	Not FDA-approved — research compound (cardioprotective signals investigated)
Typical Dose	10–25 mg orally, once daily	100 mcg, 1–2 times daily (subcutaneous)
Clinics Indexed	165	41
Categories	growth-hormone, anti-aging	growth-hormone, recovery

Key reported benefits — MK-677

✓Sustained GH/IGF-1 elevation
✓Sleep depth
✓Lean mass
✓Bone density

Key reported benefits — Hexarelin

✓Strongest GH spike of GHRPs
✓Cardioprotective signals
✓Recovery

Educational use only

This comparison is for educational purposes and not medical advice. Peptide selection should be made with a licensed medical professional based on your individual goals, health history, and current evidence quality.

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