Cetrorelix
Aliases: Cetrotide
Last verified: 2026-09-23
The short version
A GnRH antagonist — prevents premature LH surge during controlled ovarian stimulation (IVF).
Identity & type
- Molecular type
- peptide
- Origin
- A GnRH antagonist — prevents premature LH surge during controlled ovarian stimulation (IVF).
Mechanism of action
Competitive GnRHR blockade.
Dosing & routes
Official / clinical context
Approved drug — indications, dosing and warnings are defined by the official label. 0.25 mg SC daily or 3 mg once.
Regulator-approved labeling and published study designs — never a recommendation.
Community-reported practice
0.25 mg SC daily or 3 mg once. In IVF protocols prevents premature LH surge; patients tolerate it well, short course.
Unverified self-reports. Not medical advice. Not endorsement.
Expected effects (community)
In IVF protocols prevents premature LH surge; patients tolerate it well, short course.
Protocol — official vs community
Official / label
Cetrotide (controlled ovarian stimulation in IVF): 0.25 mg SC once daily, started on stimulation day 5–6 and continued until the day of hCG trigger; or 3 mg SC as a single dose, with additional 0.25 mg daily dosing if the antagonist window is exceeded.
Duration: Days-long — spans the ovarian stimulation phase only, typically 4–10 days.
Blocks the premature LH surge without a flare phase, which is precisely why antagonist protocols replaced agonist down-regulation for most patients. Administered within monitored IVF cycles; no outpatient self-directed protocol exists.
Community (anecdotal)
Structured protocol data for this entry is coming.
Human evidence
Standard IVF protocol.
Preclinical evidence
The preclinical phase was completed and submitted to regulators as part of registration; pharmacology and toxicology details are part of the official label.
Known risks
- Mild local reactions, nausea.characterized
Teal: characterized in clinical/labeling contexts. Amber: theoretical or reported outside controlled settings.
Unknowns & evidence gaps
- Real-world data outside controlled trials