cetrorelix

Action and Spectrum

Actions and spectrum: 

cetrorelix is a medication that belongs to gonadotropin-releasing hormone (GnRH) antagonists. It acts by blocking the action of GnRH in the pituitary gland, which in turn inhibits the luteinizing hormone (LH) and follicle-stimulating hormone (FSH) release. This results in the suppression of the hormonal signals that regulate the production of estrogen and progesterone in the body. 

The spectrum of action of cetrorelix is primarily focused on its use in assisted reproductive technology (ART) procedures, specifically in controlled ovarian stimulation. It is used in women to prevent premature ovulation undergoing in vitro fertilization (IVF) or other assisted reproduction techniques. By inhibiting the surge of LH that triggers ovulation, cetrorelix helps to ensure that the timing of egg retrieval is controlled and optimized for the success of the reproductive procedure. 

Drug Interaction

Adverse Reaction

Frequency defined 

<1% 

Itching 

Swelling 

Hypotension 

Cough 

Injection site erythema 

Pruritus 

Redness 

Rash  

1-10% 

Nausea (1%) 

Headache (1%) 

Ovarian hyperstimulation syndrome (4%) 

elevation of Hepatic enzyme (1-2%) 

Black Box Warning

Black Box Warning: 

There are no black box warnings specifically associated with cetrorelix 

Contraindication / Caution

Contraindication/Caution: 

Contraindication: 

• Pregnancy: cetrorelix is contraindicated during pregnancy. It should not be used in individuals who are pregnant or suspected to be pregnant, as it may have potential risks to the developing fetus. 
• Breastfeeding: cetrorelix is not recommended for use while breastfeeding. It is unknown whether cetrorelix passes into breast milk, and potential effects on the nursing infant are not well-established. 
• Severe kidney or liver impairment: cetrorelix should be used with caution in individuals with severe kidney or liver impairment, as there is limited information available regarding its safety and effectiveness in this population. 
• Pre-existing hormone-related cancers: cetrorelix is contraindicated in individuals with known or suspected hormone-related cancers such as breast, ovarian, or prostate cancer. 
• Uncontrolled thyroid or adrenal gland disorders: cetrorelix should not be used in individuals with uncontrolled thyroid or adrenal gland disorders, as it may affect hormone regulation in these conditions. 

Caution: 

• Ovarian hyperstimulation syndrome (OHSS): cetrorelix, like other medications used for controlled ovarian stimulation, may increase the risk of OHSS. This condition can cause enlarged ovaries, fluid retention, abdominal pain, and other symptoms. Close monitoring by a healthcare professional is necessary to minimize the risk and manage any potential complications. 
• Allergic reactions: Although rare, allergic reactions to cetrorelix can occur. Individuals should be monitored for signs of allergic reactions, such as rash, itching, swelling, dizziness, or difficulty breathing. If any of these symptoms occur, medical attention should be sought immediately. 
• Use in combination with other fertility medications: cetrorelix is often used in conjunction with other fertility medications. It is important to follow the prescribed treatment regimen and any specific instructions provided by the healthcare professional. Close monitoring and coordination of medication timing are necessary to optimize treatment outcomes and minimize the risk of adverse effects. 
• Interactions with other medications: cetrorelix may interact with certain medications. It is important to inform the healthcare professional about all medications, including prescription, over the counter, and herbal supplements, being taken concurrently. 
• Multiple pregnancies: Controlled ovarian stimulation treatments, including the use of cetrorelix, can increase the risk of multiple pregnancies (e.g., twins, triplets). This can pose additional health risks for both the mother and the babies. The healthcare professional will monitor the response to treatment and adjust the medication as needed to minimize the risk of multiple pregnancies. 

Comorbidities: 

• Polycystic ovary syndrome (PCOS): Women with PCOS may require special consideration and monitoring during controlled ovarian stimulation with cetrorelix due to the potential for hyperstimulation and the presence of hormonal imbalances. 
• Thyroid disorders: Individuals with thyroid disorders, such as hypothyroidism or hyperthyroidism, may need close monitoring and potential adjustment of thyroid hormone medication during fertility treatment with cetrorelix. 
• Diabetes: For individuals with diabetes, careful monitoring of blood sugar levels and potential adjustments to diabetes medications may be necessary during fertility treatment. 
• Cardiovascular conditions: Individuals with pre-existing cardiovascular conditions, such as hypertension or heart disease, may require additional monitoring and close management during controlled ovarian stimulation. 
• Blood clotting disorders: If a person has a known blood clotting disorder or a history of thromboembolic events, special caution and monitoring may be required during fertility treatment with cetrorelix. 

Pregnancy / Lactation

Pregnancy consideration: US FDA pregnancy category: X 

Lactation: Excreted into human milk: Unknown  

Pregnancy category: 

• Category A: well-controlled and Satisfactory studies show no risk to the fetus in the first or later trimester. 
• Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women. 
• Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.   
• Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits. 
• Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women. 
• Category N: There is no data available for the drug under this category. 

Pharmacology

Pharmacology: 

cetrorelix is a synthetic peptide analogue of gonadotropin-releasing hormone (GnRH) that acts as a competitive antagonist at the GnRH receptors in the pituitary gland. GnRH normally stimulates the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) from the pituitary gland, which play important roles in the regulation of reproductive function. 

By acting as a GnRH receptor antagonist, cetrorelix inhibits the LH and FSH release from the pituitary gland. This suppression of LH and FSH prevents premature ovulation in women undergoing controlled ovarian stimulation for assisted reproductive techniques like in vitro fertilization. By suppressing premature ovulation, it allows for the optimal timing of follicle maturation and retrieval during the IVF process.  

Pharmacodynamics: 

The pharmacodynamics of cetrorelix primarily involves its action as a competitive antagonist at the gonadotropin-releasing hormone (GnRH) receptors in the pituitary gland. By binding to these receptors, cetrorelix prevents the binding of endogenous GnRH, thereby inhibiting the luteinizing hormone (LH) and follicle-stimulating hormone (FSH) release. 

The inhibition of LH and FSH release by cetrorelix has several important effects in the context of assisted reproductive technology (ART) procedures. It prevents premature ovulation, allowing for the precise timing of follicle maturation and retrieval during procedures such as in vitro fertilization (IVF). This ensures that the eggs are retrieved at the optimal stage of development for successful fertilization. 

cetrorelix also helps to prevent the luteinizing hormone surge that can occur during controlled ovarian stimulation, which could lead to the release of multiple eggs and increase the risk of ovarian hyperstimulation syndrome (OHSS).  

Pharmacokinetics: 

Absorption 

cetrorelix is administered subcutaneously, meaning it is injected into fatty tissue beneath the skin. The drug gets rapidly absorbed into the bloodstream after subcutaneous injection. 

Distribution 

cetrorelix is distributed throughout the body via the bloodstream. It has a relatively large volume of distribution, indicating that it distributes widely into the tissues. 

Metabolism 

cetrorelix is not extensively metabolized in the body. It is primarily eliminated unchanged via renal excretion. Metabolic pathways, if any, are likely to be minor. 

Elimination and excretion 

cetrorelix is primarily excreted in the urine. The drug has short elimination half-life of about 3 to 4 hours, meaning it is cleared from the body within a few hours after administration. 

Adminstartion

Administration: 

• Preparation: cetrorelix comes as a powder or a pre-filled syringe, which may require reconstitution or preparation before administration.  
• Site selection: Choose an appropriate injection site, such as the lower abdomen or thigh. Rotate the injection sites to minimize the risk of local skin reactions. 
• Injection technique: Use a sterile needle and syringe for the injection. Follow proper aseptic technique to minimize the risk of infection. The healthcare professional may provide instructions on the proper injection technique. 
• Dosage and schedule: The dosage and dosing schedule of cetrorelix will depend on the specific indication and individual patient factors. Follow the prescribed dose and schedule provided by the healthcare professional. Do not modify the dosage or schedule without consulting the healthcare professional. 
• Storage: Follow the storage instructions provided by the manufacturer or healthcare professional. Some formulations of cetrorelix may require refrigeration, while others may be stored at room temperature. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: cetrorelix 

Pronounced: (Seh-troh-REL-ix)  

Why do we use cetrorelix? 

• Women undergoing intracytoplasmic sperm injection (ICSI) or in vitro fertilization (IVF): cetrorelix is used to prevent premature ovulation to allow for optimal timing of oocyte retrieval during ART procedures. By suppressing the natural surge of luteinizing hormone (LH), it helps to maintain control over the timing of follicle maturation. 
• Prevention of premature LH surge during controlled ovarian stimulation: cetrorelix helps prevent the spontaneous release of LH during controlled ovarian stimulation. This helps to prevent the premature release of eggs and allows for better control over the fertility treatment process. 
• Suppression of premature luteinizing hormone (LH) surge during ovarian stimulation: cetrorelix acts as a GnRH antagonist, blocking the effects of endogenous GnRH and suppressing the release of LH. This helps to regulate the ovarian response during ovarian stimulation, reducing the risk of premature LH surge and improving the chances of successful fertilization and implantation.