What is the difference between MK-677 and GHRH (1–44)?

MK-677 (Ibutamoren (MK-677)) is graded B+ and is Not FDA-approved — investigational (orally active GH secretagogue). GHRH (1–44) (Growth Hormone Releasing Hormone, full sequence) is graded A and is FDA-approved (Geref) historically as diagnostic GH stimulant; current US availability limited. They are commonly compared because they share the categories: growth-hormone.

Which has stronger clinical evidence — MK-677 or GHRH (1–44)?

On our internal evidence scale, MK-677 is B+ and GHRH (1–44) is A. A+ indicates large RCTs plus FDA approval; C indicates primarily preclinical or anecdotal evidence.

What is the typical dose of MK-677 vs GHRH (1–44)?

MK-677: 10–25 mg orally, once daily. GHRH (1–44): 1 mcg/kg IV (diagnostic test). Always work with a licensed clinician — peptide dosing should be individualized.

MK-677 vs GHRH (1–44)

Both MK-677 and GHRH (1–44) 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.

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GHRH (1–44)

Evidence A

Growth Hormone Releasing Hormone, full sequence

The full 44-amino-acid GHRH sequence. The natural pituitary stimulus for GH release. Largely supplanted in clinical use by sermorelin/tesamorelin but remains a research and diagnostic tool.

View full GHRH (1–44) profile →

Side-by-Side

Attribute	MK-677	GHRH (1–44)
Evidence Grade	B+	A
FDA Status	Not FDA-approved — investigational (orally active GH secretagogue)	FDA-approved (Geref) historically as diagnostic GH stimulant; current US availability limited
Typical Dose	10–25 mg orally, once daily	1 mcg/kg IV (diagnostic test)
Clinics Indexed	165	22
Categories	growth-hormone, anti-aging	growth-hormone

Key reported benefits — MK-677

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

Key reported benefits — GHRH (1–44)

✓Endogenous GH stimulation
✓Diagnostic GH testing

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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