Compound Profile · Hormone Signaling / GH-Axis Hub
Ibutamoren · MK-0677 · Oral ghrelin-mimetic growth-hormone secretagogue
The one that isn't a peptide and isn't a steroid — an oral pill that mimics ghrelin, the hunger hormone, to make your own pituitary release more growth hormone. It reliably raises IGF-1. It also reliably raises appetite, water weight, and blood sugar. This profile gives you both halves honestly.
Why This Page Exists
MK-677 gets sold two ways, both wrong: as a harmless "GH in a pill" by people who want your money, and as a dangerous drug by people who've never read the human data. The truth is narrower and more useful. It genuinely and durably raises growth hormone and IGF-1 by mouth — a real pharmacological effect. And it genuinely raises appetite, holds water, and nudges blood sugar the wrong way. Whether that trade is worth it depends entirely on who you are, which is exactly what a screen is for.
Regulatory Status
MK-677 was studied in clinical trials (including in older adults and catabolic states) but never FDA-approved for any indication. It is sold as a research compound only.
MK-677 is not a legal dietary-supplement ingredient, though it is widely and improperly sold as one. Products vary enormously in actual content.
An orally active non-peptide. It's grouped with peptides only because it acts on the growth-hormone axis; chemically and practically it's a different kind of compound.
MK-677 is on the WADA Prohibited List as a growth-hormone secretagogue. Tested athletes must not use it.
Mechanism of Action
MK-677 activates the ghrelin receptor (GHSR) in the pituitary and hypothalamus, prompting release of the body's own growth hormone in a pulsatile, physiological pattern — rather than injecting GH directly.
MK-677 → ghrelin receptor (GHSR) → pituitary GH pulse → ↑ IGF-1 from the liverUnlike some secretagogues where the effect fades, oral MK-677 raises GH and IGF-1 durably with daily dosing in human studies. That sustained IGF-1 elevation drives the sought-after effects on sleep, recovery, and lean mass — and several of the cautions.
Because ghrelin is the hunger hormone, activating its receptor drives a strong increase in appetite. For someone underweight or catabolic that's a feature; for someone managing weight it's a liability. Same mechanism, opposite value depending on the goal.
Elevated GH/IGF-1 signaling can reduce insulin sensitivity and raise fasting glucose. This is the single most important trade-off, and the reason MK-677 is screened hard against any diabetes, pre-diabetes, or metabolic-syndrome history.
Primary Use Cases
Evidence Snapshot
| Domain | Type | Key finding |
|---|---|---|
| GH / IGF-1 elevation | Human RCT | Oral MK-677 durably raises GH and IGF-1 in adults, sustained over months of daily dosing. |
| Older-adult & catabolic studies | Clinical | Increased lean mass and IGF-1; studied in aging and hip-fracture recovery contexts. |
| Glucose metabolism | Human | Reduced insulin sensitivity and increased fasting glucose observed — a consistent, dose-relevant signal. |
| Body composition (recreational use) | Anecdotal | Widely reported water weight, appetite, and sleep effects; lean-mass claims exceed the controlled data. |
Protocols
Educational reference only — MK-677 is investigational and its metabolic effects warrant physician oversight and glucose monitoring.
Taken once daily by mouth; the long half-life means once-a-day covers 24 hours. Lower doses (10 mg) reduce appetite and water effects; higher doses amplify both.
Often taken before bed to align GH pulse with sleep, though some shift to morning if evening dosing worsens grogginess or water retention. Consistency matters more than the exact hour.
Red Flags & Cautions
Common Questions
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