What is the difference between Cetrorelix and Leuprolide?

Cetrorelix: Competitive GnRH receptor antagonist; immediately blocks pituitary GnRH receptors; rapidly suppresses LH/FSH without initial flare effect; used for controlled hormonal suppression Leuprolide: Continuous GnRH receptor stimulation causes receptor desensitization and downregulation. This suppresses LH/FSH → testosterone/estrogen to castrate levels.

Is Cetrorelix FDA approved?

Cetrorelix is FDA approved. This regulatory status is provided for research and educational context only.

Is Leuprolide FDA approved?

Leuprolide is FDA approved (FDA status current as of 1985-04-08). This regulatory status is provided for research and educational context only.

How is Cetrorelix administered in research settings?

In research settings, Cetrorelix is typically administered via the subcutaneous route. PeptideBase does not provide dosing or administration instructions.

How is Leuprolide administered in research settings?

In research settings, Leuprolide is typically administered via the subcutaneous, intramuscular, or implant routes. PeptideBase does not provide dosing or administration instructions.

Home›Research›Compare›Cetrorelix vs Leuprolide

Peptide Comparison

Cetrorelix vs Leuprolide

Both are Reproductive & Hormonal peptides.

Cetrorelix

Cetrotide

Sexual HealthFDA ApprovedPrescription

Half-life: ~62 hours

1 providers listed

Full Cetrorelix profile →

Leuprolide

Lupron

Sexual HealthFDA ApprovedPrescription

2 providers listed

Full Leuprolide profile →

Bottom line

Leuprolide is carried by more providers on PeptideBase (2 vs 1); otherwise the two are closely matched on the measures we track.

Quick Verdict

Cetrorelix

Half-life

~62 hours

Leuprolide

Half-life

—

Which One Should You Choose?

Your goal	Better option
More provider options (1 vs 2)	Leuprolide

Research summary only — not medical advice. Consult a qualified provider before making any decisions.

Side-by-Side Comparison

Cetrorelix

Leuprolide

Mechanism Family

Reproductive & Hormonal

Half-life

~62 hours

—

FDA Status

approved

Admin Routes

subcutaneous

subcutaneous, intramuscular, implant

Availability

Prescription

Providers

1 listed

2 listed

FDA Update

—

Apr 1985

Avail. Notes

FDA-approved GnRH antagonist. Brand: Cetrotide (NDA 021036, Jun 1999). Prevents premature LH surges in controlled ovarian stimulation. Prescription only.

FDA-approved: Lupron (leuprolide acetate), Drugs@FDA application 019010.

Research Evidence

Cetrorelix

Meta-analysis · 7 key studies · most recent 2026

Leuprolide

Meta-analysis · 8 key studies · most recent 2026

Research Citations

Cetrorelix

Meta-analysis2026 · J Coll Physicians Surg Pak

GnRH Agonists and Antagonists in IVF/ICSI Cycles of PCOS Women: A Network Meta-Analysis.

Meta-analysis2023 · Hum Reprod Update

Optimal GnRH antagonist protocol for ovarian stimulation during ART: systematic review and network meta-analy…

Cohort2026 · Int J Reprod Biomed

Efficacy and safety of different cetrorelix doses in the luteal phase for preventing ovarian hyperstimulation…

Cohort2021 · BMC Pregnancy and Childbirth

Effects of half-dose and full-dose GnRH antagonists on IVF-ET outcomes: a retrospective study

+3 more

Leuprolide

Meta-analysis2024 · J Minim Invasive Gynecol

The Effect of Hormonal Treatment on Ovarian Endometriomas: A Systematic Review and Meta-Analysis

RCT2009 · Am J Obstet Gynecol

Add-back estradiol/progesterone to GnRH agonist in PMDD

RCT1993 · Am J Obstet Gynecol

Depot leuprolide vs danazol for endometriosis: multicenter double-blind RCT

RCT1984 · New England Journal of Medicine

Leuprolide versus diethylstilbestrol for metastatic prostate cancer

+4 more

About Cetrorelix

Competitive GnRH receptor antagonist; immediately blocks pituitary GnRH receptors; rapidly suppresses LH/FSH without initial flare effect; used for controlled hormonal suppression

Research Areas

HPG axis suppressionLH/FSH reductioncontrolled ovarian stimulation supporttestosterone management

About Leuprolide

Continuous GnRH receptor stimulation causes receptor desensitization and downregulation. This suppresses LH/FSH → testosterone/estrogen to castrate levels. Short-term pulsatile use can transiently stimulate the axis before suppression occurs.

Research Areas

HPG axis modulationtestosterone suppressionhormonal restartGnRH axis control

Safety Profile

Information below reflects published research data only — not medical advice. Consult a qualified provider before use.

Cetrorelix

Absolute Contraindications

Pregnancy — contraindicatedLactation — contraindicated

Source: FDA label

Suggested Monitoring

Under clinical review

Being verified by our medical team before we display monitoring guidance for this peptide.

Leuprolide

Absolute Contraindications

Under clinical review

Being verified by our medical team before we display contraindications for this peptide.

Suggested Monitoring

Under clinical review

Being verified by our medical team before we display monitoring guidance for this peptide.

Find Providers

Where to source these peptides

Providers offering

Cetrorelix

1 listed

Browse directory →

Providers offering

Leuprolide

2 listed

Browse directory →

PeptideBase lists providers for educational research purposes only. Always consult a qualified healthcare professional before obtaining or using any peptide.

More Reproductive & Hormonal Comparisons

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Educational research tools — not medical advice.