Hexarelin vs MK-677 (Ibutamoren)

Name: Hexarelin vs MK-677 (Ibutamoren)
Published: 2026-10-24

Updated Oct 24, 202613 sources

Key differences

1MK-677 is an oral small molecule with all-day action; hexarelin is an injected peptide with a short pulse.
2Both hit the same ghrelin receptor, so guides call taking them together redundant.
3Hexarelin is an injected peptide with a short, strong pulse that fades with daily use; MK-677 is oral and works all day.
4Both hit the ghrelin receptor, so guides do not stack them.

Facts from each record, in the same words as their own pages.

Hexarelin and MK-677 (Ibutamoren) side by side
	Hexarelin	MK-677 (Ibutamoren)
Category	GH axis	GH axis
Evidence	Limited human data	Some human trials
FDA status	Not FDA approvedRegulatory	FDA 503A Category 2Regulatory
WADA	Prohibited	Prohibited
Half-life	About 55 minutes, per a 2026 review. The 1994 study it cites gave 55 minutes for the fall in blood GH after a dose, so the figure describes the GH response more than the peptide itself.Clinical study About 70 minutes in plasma, per guides.Competitor guide	About 4 to 6 hours, measured in beagles; no human plasma half-life in the sources.Reference work About 24 hours, per most guides. That figure tracks how long the effect lasts more than plasma levels.Competitor guide
Routes	Subcutaneous injection, Intravenous (IV), Nasal	Oral
Forms	Vial (powder)	Capsule, Oral solution
Reported doses	50 to 300 mcg (subcutaneous injection) 1.5 mcg/kg (subcutaneous injection) 0.5 to 2 mcg/kg (intravenous (iv))	2 to 25 mg (oral) 0.8 to 3.2 mg/kg (oral)
Most cited frequency	1 to 2 times a day	Once daily
Vial sizes	2 mg, 5 mgCompetitor guide	Not reported
Mixed vial keeps	Fridge, 2 to 8 °C; never freeze.Competitor guide	Not reported
Protocols on file	16	16

Doses shown are what sources report, labelled by origin. Not medical advice.

13 sources, each checked by date. Record updated Oct 24, 2026. Numbers are restated in our own words and labelled by where they came from.