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PeptideHormone

Cetrorelix

A GnRH antagonist — immediate suppression with no flare.

Also known as Cetrotide.

AnalogEstablishedBased on Gonadotropin-releasing hormoneCompare with GnRH Compare lineage

Blocking the receptor outright rather than exhausting it — the same endpoint reached without the flare that precedes it.

Identity

Class
GnRH receptor antagonist (decapeptide)
Source
Synthetic GnRH antagonist
Receptor
GnRH receptor (GnRHR) — competitive antagonist

Key properties

Evidence floorClinicalREF1CLIN1
Molecular weight
~1,431 Da
REF
Half-life (native)
~5 h (immediate-release)
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

Cetrorelix blocks the GnRH receptor directly, so it suppresses gonadotropin release immediately and without the initial flare that agonists cause. This clean, rapid suppression is the key mechanistic contrast with agonists like leuprolide.

Reference notes

  • As an antagonist, it produces immediate suppression — no agonist flare.
  • It is the mechanistic mirror image of GnRH agonists at the same receptor.
  • The flare-vs-no-flare difference is a clear teaching case in receptor pharmacology.

Common questions

What is Cetrorelix?
A GnRH antagonist — immediate suppression with no flare. Structurally it is GnRH receptor antagonist (decapeptide).
How does Cetrorelix work?
Cetrorelix blocks the GnRH receptor directly, so it suppresses gonadotropin release immediately and without the initial flare that agonists cause. This clean, rapid suppression is the key mechanistic contrast with agonists like leuprolide.
How strong is the evidence for Cetrorelix?
PeptideHormone grades Cetrorelix at the "Established" evidence tier — its mechanism and core effects are settled across the peer-reviewed literature. It is catalogued as an engineered analog built on an endogenous hormone, and the tier is an editorial judgment about the public literature that can change as the science does.
What is the half-life of Cetrorelix?
The reported circulating half-life of Cetrorelix is ~5 h (immediate-release).
Is Cetrorelix the same as Cetrotide?
Cetrotide is a brand name of Cetrorelix — the same molecule in different approved presentations. This page is the molecule reference, not a prescribing guide.

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. 1.The LHRH antagonist cetrorelix: a review · Human reproduction update, 2000 · PMID 10972520
  2. 2.LHRH antagonists · Pharmaceutical biotechnology, 1998 · PMID 9760679

External references

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