Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
CETROTIDE vs DEGARELIX ACETATE
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Cetrorelix is a synthetic decapeptide with gonadotropin-releasing hormone (Gn RH) antagonistic activity. It competitively blocks Gn RH receptors on the pituitary gland, reducing the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH).
Gonadotropin-releasing hormone (Gn RH) receptor antagonist; competitively and reversibly binds to Gn RH receptors in the anterior pituitary, rapidly suppressing luteinizing hormone (LH) and follicle-stimulating hormone (FSH) secretion, thereby reducing testosterone production.
Inhibition of premature LH surges in women undergoing controlled ovarian stimulation for assisted reproductive technology (ART)
Treatment of advanced prostate cancer
0.25 mg subcutaneously once daily starting on day 7 of ovarian stimulation and continuing until the day of h CG administration.
Subcutaneous injection: 240 mg loading dose (two 120 mg injections) on day 1, followed by 80 mg every 28 days.
Terminal elimination half-life is approximately 36 hours after subcutaneous administration. This long half-life supports once-daily dosing for continuous Gn RH antagonist effect.
Terminal elimination half-life is approximately 43-73 days after subcutaneous administration, reflecting slow release from the depot formulation.
Cetrorelix is metabolized via peptidase cleavage and is primarily eliminated unchanged in urine and feces.
Hepatic via hydrolysis of the acetate ester; no significant CYP450 involvement.
Primarily 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.
Renal elimination accounts for approximately 20-30% of the dose as unchanged drug; fecal elimination accounts for 70-80% primarily as metabolites.
Approximately 80% bound to plasma proteins, primarily albumin.
Approximately 90% bound to plasma proteins, primarily albumin and alpha-1-acid glycoprotein.
Approximately 0.7 L/kg, indicating distribution primarily into extracellular fluid and limited tissue binding.
Approximately 1 L/kg, indicating extensive distribution into tissues.
Subcutaneous administration: approximately 85% absolute bioavailability compared to intravenous injection.
Subcutaneous: approximately 100% for the depot formulation; not available orally due to peptide degradation.
No specific dose adjustment is recommended for patients with renal impairment; however, caution is advised in severe impairment due to limited data.
No dose adjustment required for GFR ≥15 m L/min. Insufficient data for GFR <15 m L/min or dialysis; use caution.
No specific dose adjustment is recommended for patients with hepatic impairment; however, caution is advised in severe impairment due to limited data.
No dose adjustment required for mild to moderate hepatic impairment (Child-Pugh A or B). Not studied in severe impairment (Child-Pugh C).
Not indicated for pediatric use; safety and efficacy have not been established.
Safety and efficacy not established in pediatric patients; no recommended dosing.
Not indicated for geriatric use; safety and efficacy have not been established in women over 65 years.
No specific dose adjustment required; similar efficacy and safety observed in elderly patients (≥65 years) compared to younger adults.
None.
None
Hypersensitivity 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.
Hypersensitivity reactions including anaphylaxis and angioedema,QT interval prolongation,Laboratory test interference with gonadotropin and gonadal steroid assays,Injection site reactions including pain and erythema,Bone density loss,Hyperglycemia and increased risk of diabetes
Hypersensitivity to cetrorelix, Gn RH, or any other Gn RH analog.,Known or suspected pregnancy.,Breastfeeding.,Severe renal impairment (creatinine clearance <30 m L/min).,Pre-existing moderate to severe hepatic impairment.
Hypersensitivity to degarelix or any component of the formulation,Pregnancy (potential fetal harm)
No known food interactions. No dietary restrictions required.
No specific food interactions have been identified. Degarelix is administered parenterally and does not interact with dietary components. Avoid grapefruit juice if concurrent QT-prolonging drugs are used, but not a direct interaction with degarelix.
Pregnancy 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.
Category X: Contraindicated in pregnancy. First trimester: Risk of spontaneous abortion and congenital anomalies due to hormonal disruption. Second and third trimesters: Potential for fetal androgen deprivation leading to ambiguous genitalia in male fetuses.
No data on cetrorelix excretion in human milk. M/P ratio unknown. Given its peptide nature and short half-life, excretion is unlikely but not confirmed. Caution advised; avoid use in nursing mothers unless clearly needed.
No data available on excretion in human milk; potential for serious adverse effects in nursing infants; discontinue breastfeeding or discontinue drug.
Cetrorelix is contraindicated in pregnancy; no dosing adjustments apply. Dose modifications are not recommended as drug should not be used.
No dose adjustments are applicable as degarelix is contraindicated in pregnancy; therapy must be discontinued if pregnancy occurs.
Cetrotide (cetrorelix) is a Gn RH 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 Gn RH agonists. Dose adjustment not required in renal or hepatic impairment. Use with caution in patients with allergies to Gn RH analogs or mannitol.
Degarelix acetate is a Gn RH antagonist used for advanced prostate cancer. It provides rapid testosterone suppression without the initial testosterone surge seen with Gn RH agonists. Monitor serum testosterone and PSA levels; castrate levels (<50 ng/d L) typically achieved within 3 days. Injection site reactions are common; rotate injection sites (abdomen, thigh, buttock). Avoid in patients with known QT prolongation or concurrent QT-prolonging drugs. Contraindicated in women and children.
Inject 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.
Degarelix is given as a subcutaneous injection by a healthcare provider every month (or every 2 months for maintenance dose) to treat advanced prostate cancer.,Do not miss scheduled injections because consistent dosing is needed to keep testosterone levels low.,Common side effects include injection site pain, redness, or swelling; hot flashes; increased liver enzymes; and weight gain.,Report signs of allergic reaction (rash, itching, difficulty breathing) or prolonged QT interval (fainting, palpitations) to your doctor immediately.,Degarelix may cause bone thinning; discuss calcium and vitamin D supplementation with your doctor.,This drug can cause harm to a fetus; not for use in women or children.
No interactions on record
"Asenapine, a second-generation antipsychotic, is associated with dose-dependent QTc interval prolongation due to its inhibitory effects on cardiac potassium channels (specifically IKr). Degarelix, a GnRH antagonist used in prostate cancer, may also cause QTc prolongation, likely through hormonal suppression mechanisms. Coadministration can result in additive QTc prolongation, increasing the risk of torsade de pointes and other ventricular arrhythmias, especially in patients with pre-existing risk factors."
"Dolasetron, a 5-HT3 receptor antagonist, is known to cause dose-dependent prolongation of the QT interval by blocking cardiac potassium channels. When coadministered with Degarelix, a GnRH receptor antagonist that also reduces testosterone levels and can induce QT prolongation via electrolyte disturbances (e.g., hypokalemia, hypomagnesemia) or direct cardiac effects, the risk of additive QT prolongation is increased. This may lead to a higher propensity for torsade de pointes and other ventricular arrhythmias, particularly in patients with pre-existing risk factors."
"Cabazitaxel is a taxane antineoplastic agent that undergoes extensive hepatic metabolism via CYP3A4/5 and is a substrate of P-glycoprotein. Degarelix, a GnRH antagonist, has no known direct metabolic interaction with Cabazitaxel but may theoretically increase the risk of QT prolongation when combined with other drugs. However, the baseline description is vague; the interaction is not well-established and possibly refers to additive myelosuppression or cardiovascular effects from overlapping toxicities."
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about CETROTIDE vs DEGARELIX ACETATE, answered by our medical review team.
CETROTIDE is a GnRH antagonist that works by Cetrorelix is a synthetic decapeptide with gonadotropin-releasing hormone (Gn RH) antagonistic activity. It competitively blocks Gn RH receptors on the pituitary gland, reducing the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH).. DEGARELIX ACETATE is a GnRH antagonist that works by Gonadotropin-releasing hormone (Gn RH) receptor antagonist; competitively and reversibly binds to Gn RH receptors in the anterior pituitary, rapidly suppressing luteinizing hormone (LH) and follicle-stimulating hormone (FSH) secretion, thereby reducing testosterone production.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between CETROTIDE and DEGARELIX ACETATE depend on the specific clinical indication. These are both GnRH antagonist agents and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of CETROTIDE is: 0.25 mg subcutaneously once daily starting on day 7 of ovarian stimulation and continuing until the day of h CG administration.. The standard adult dose of DEGARELIX ACETATE is: Subcutaneous injection: 240 mg loading dose (two 120 mg injections) on day 1, followed by 80 mg every 28 days.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between CETROTIDE and DEGARELIX ACETATE in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. CETROTIDE is classified as Category C. Pregnancy 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 . DEGARELIX ACETATE is classified as Category C. Category X: Contraindicated in pregnancy. First trimester: Risk of spontaneous abortion and congenital anomalies due to hormonal disruption. Second and third trimesters: Potential . Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.