Paces the migrating motor complex between meals. Structurally it is Gut peptide (22 aa).

How strong is the evidence for Motilin?

PeptideHormone grades Motilin at the "Established" evidence tier — its mechanism and core effects are settled across the peer-reviewed literature. It is catalogued as an endogenous signal the body produces itself, and the tier is an editorial judgment about the public literature that can change as the science does.

What is the half-life of Motilin?

The reported circulating half-life of Motilin is ~4–5 min.

Is Motilin FDA-approved?

No — as of September 2026, Motilin is a native hormone with no drug product of its own, though engineered analogs may be approved. No motilin product; erythromycin is used off-label as a motilin-receptor agonist. Status is US-centric and can change; check the FDA record for the current position.

Motilin

Paces the migrating motor complex between meals.

EndogenousEstablishedEndogenous signal

The housekeeping signal between meals — evidence that the gut has work to do precisely when it has nothing to digest.

Identity

Class: Gut peptide (22 aa)
Source: Endocrine cells of the small intestine
Receptor: Motilin receptor (a class A GPCR)

Key properties

Evidence floorClinicalREF1CLIN1

Molecular weight

~2,698.1 Da

REF

Half-life (native)

~4–5 min

CLIN

Model dosing

Approximate values for the native hormone; engineered analogs are often deliberately larger and far longer-acting. Each figure carries its own provenance tier, and the floor is the weakest of them - the Standard.

Mechanism

Motilin is released cyclically in the fasting state and drives the migrating motor complex — the rhythmic 'housekeeping' contractions that sweep residual contents through the gut between meals. Its role is timing, distinct from the post-meal satiety peptides.

Reference notes

Motilin governs the fasting (interdigestive) motility pattern, not the fed state.
Certain macrolide antibiotics act as motilin-receptor agonists — an off-target pharmacology.
Its between-meal role distinguishes it from the post-meal gut peptides.

Regulatory status

United States · reviewed September 2026

Endogenous signalMotilin is a native hormone with no drug product of its own, though engineered analogs may be approved.

Basis: No motilin product; erythromycin is used off-label as a motilin-receptor agonist.

Status describes the molecule as a drug substance under US law and is an editorial reading of the public record — approvals, trial registrations, and the FDA 503A bulk-substances list. It is not legal advice and it changes; the review date above is the last time the table was checked. Other jurisdictions are noted only where they differ materially.

Common questions

What is Motilin?: Paces the migrating motor complex between meals. Structurally it is Gut peptide (22 aa).
How does Motilin work?: Motilin is released cyclically in the fasting state and drives the migrating motor complex — the rhythmic 'housekeeping' contractions that sweep residual contents through the gut between meals. Its role is timing, distinct from the post-meal satiety peptides.
How strong is the evidence for Motilin?: PeptideHormone grades Motilin at the "Established" evidence tier — its mechanism and core effects are settled across the peer-reviewed literature. It is catalogued as an endogenous signal the body produces itself, and the tier is an editorial judgment about the public literature that can change as the science does.
What is the half-life of Motilin?: The reported circulating half-life of Motilin is ~4–5 min.
Is Motilin FDA-approved?: No — as of September 2026, Motilin is a native hormone with no drug product of its own, though engineered analogs may be approved. No motilin product; erythromycin is used off-label as a motilin-receptor agonist. Status is US-centric and can change; check the FDA record for the current position.

In the literature

Live registry counts · retrieved 2026-09-15

Registered trialsREF

Ph 12
Ph 25
Ph 30
Ph 45

Open on ClinicalTrials.gov

Searched as Motilin. Counts are search hits from the primary registries, not a curated set and not a grade – a measure of how much work exists on Motilin, not how it turned out.

Selected literature

Curated peer-reviewed reviews, sourced from PubMed. Selected for relevance, not exhaustive — open any entry on PubMed for the full record and its primary citations.

1.Motilin and clinical application · Peptides, 1997 · PMID 9210180
2.The gastrointestinal tract in hunger and satiety signalling · United European gastroenterology journal, 2021 · PMID 34153172

External references

Motilin in the public knowledge graph — the same entity resolved across the authoritative chemistry and protein databases.