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GnRH antagonist/Discontinued

CETROTIDE

CETROTIDE

Clinical safety rating

caution

Comprehensive clinical and safety monograph for CETROTIDE (CETROTIDE).


What is CETROTIDE?

Comprehensive clinical and safety monograph for CETROTIDE (CETROTIDE).

Indications & Uses

Inhibition of premature LH surges in women undergoing controlled ovarian stimulation for assisted reproductive technology (ART)

Compare CETROTIDE vs CETRORELIX ACETATE →View all GnRH antagonist drugs →

Mechanism of Action

Cetrorelix is a synthetic decapeptide with gonadotropin-releasing hormone (GnRH) antagonistic activity. It competitively blocks GnRH receptors on the pituitary gland, reducing the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH).

What the body does with it

MetabolismCetrorelix is metabolized via peptidase cleavage and is primarily eliminated unchanged in urine and feces.
ExcretionPrimarily renal excretion of unchanged drug (approx. 40-50%) and metabolites; remainder excreted in feces via biliary elimination. Total recovery in urine and feces accounts for >90% of dose.
Half-lifeTerminal elimination half-life is approximately 36 hours after subcutaneous administration. This long half-life supports once-daily dosing for continuous GnRH antagonist effect.
Protein bindingApproximately 80% bound to plasma proteins, primarily albumin.
Volume of DistributionApproximately 0.7 L/kg, indicating distribution primarily into extracellular fluid and limited tissue binding.
BioavailabilitySubcutaneous administration: approximately 85% absolute bioavailability compared to intravenous injection.
Onset of ActionSubcutaneous: Suppression of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) occurs within 1-2 hours, with maximal suppression achieved by 4-8 hours.
Duration of ActionSingle subcutaneous injection suppresses LH and FSH for at least 24 hours, allowing once-daily dosing. Continuous therapy maintains suppression throughout the treatment period.
Molecular Weight1431.1

Classification & Brands

Dosing & administration

0.25 mg subcutaneously once daily starting on day 7 of ovarian stimulation and continuing until the day of hCG administration.

Dosage formPOWDER
Renal impairmentNo specific dose adjustment is recommended for patients with renal impairment; however, caution is advised in severe impairment due to limited data.
Liver impairmentNo specific dose adjustment is recommended for patients with hepatic impairment; however, caution is advised in severe impairment due to limited data.
Pediatric useNot indicated for pediatric use; safety and efficacy have not been established.
Geriatric useNot indicated for geriatric use; safety and efficacy have not been established in women over 65 years.

Use during pregnancy

1st trimesterContraindicated due to risk of fetal harm; may cause pregnancy loss or congenital anomalies based on its antigonadotropic action.
2nd trimesterContraindicated; continued antigonadotropic effects may disrupt fetal development.
3rd trimesterContraindicated; may interfere with parturition or fetal pituitary-gonadal axis.

Clinical note

Comprehensive clinical and safety monograph for CETROTIDE (CETROTIDE).

Placental transferExpected to cross placenta based on molecular size and lipophilicity; documented transfer in animal studies.
BreastfeedingExcretion into human milk unknown; potential for adverse effects on infant hormonal development; avoid use during breastfeeding unless clearly necessary.
Lactation RatingL5
Teratogenic RiskPregnancy Category X. Cetrorelix is contraindicated during pregnancy due to risk of fetal harm. In animal studies, it caused embryolethality and teratogenicity at doses lower than human exposure. No adequate human studies exist.
Fetal MonitoringMonitor for signs of ovarian hyperstimulation syndrome (OHSS) during controlled ovarian stimulation. If inadvertent pregnancy occurs, discontinue cetrorelix and monitor fetal development via ultrasound.
Fertility EffectsCetrorelix is used therapeutically to prevent premature LH surges in assisted reproduction, thereby regulating fertility. It does not impair long-term fertility; ovarian function returns to baseline after discontinuation.

Warnings & precautions

■ FDA Black Box Warning

None.

Side Effect Profile

Serious Effects

Absolute Contraindications

Hypersensitivity to cetrorelix or any excipientPregnancySevere hepatic impairmentSevere renal impairment

Clinical Precautions

PrecautionsHypersensitivity reactions (e.g., anaphylaxis) have been reported., Ovarian hyperstimulation syndrome (OHSS) may occur; monitor during stimulation., Use caution in patients with active allergic conditions or history of asthma.
Food/DietaryNo known food interactions. No dietary restrictions required.

Clinical Tips & Counseling

Clinical PearlsCetrotide (cetrorelix) is a GnRH antagonist used in controlled ovarian stimulation to prevent premature LH surges. Administer subcutaneously in the lower abdominal wall; rotate sites. Monitor for ovarian hyperstimulation syndrome (OHSS). Onset of action is immediate; does not cause flare effect like GnRH agonists. Dose adjustment not required in renal or hepatic impairment. Use with caution in patients with allergies to GnRH analogs or mannitol.
Patient AdviceInject exactly as prescribed, at the same time each day during the stimulation cycle. · Do not skip doses; missing a dose may increase risk of premature ovulation. · Report any signs of allergic reaction, such as rash, hives, or difficulty breathing. · Mild injection site reactions (redness, swelling, itching) are common and usually resolve. · Avoid pregnancy prior to the procedure; use non-hormonal contraception if needed. · Understand the risk of OHSS: symptoms include severe pelvic pain, nausea, vomiting, sudden weight gain, and decreased urination.

CETROTIDE Interactions

Loading safety data…

This overview is compiled from peer-reviewed clinical sources and FDA labeling. It's here to support — not replace — clinical judgment. Always verify dosing against your institution's current protocols before prescribing.

On this page

Mechanism of ActionDosing & administrationUse during pregnancyWarnings & precautionsDrug interactions

Compare with

CETRORELIX ACETATEDEGARELIX ACETATEFIRMAGONZEGALOGUEZEGALOGUE (AUTOINJECTOR)

External sources

DailyMed (NIH) PubMed OpenFDA