Cetrorelix Acetate is used in the treatment of female infertility. It works by preventing premature ovulation and controlling the release of eggs during ovarian stimulation. By ensuring proper development of ovarian follicles and preventing early egg release, it supports the maturation of healthy eggs and improves the chances of successful pregnancy.

Cetrorelix Acetate is a synthetic decapeptide that acts as a gonadotropin-releasing hormone (GnRH) antagonist. It blocks the action of GnRH, which normally regulates the secretion of luteinizing hormone (LH) responsible for triggering ovulation. During ovarian stimulation therapy, premature LH surge can result in the release of immature eggs unsuitable for fertilization. Cetrorelix prevents this early LH surge, thereby avoiding premature ovulation.

GnRH stimulates the release of LH and follicle-stimulating hormone (FSH) from the anterior pituitary. Mid-cycle, increased estradiol (E2) levels enhance GnRH secretion, leading to an LH surge that triggers ovulation, oocyte maturation, and luteinization. Cetrorelix competitively binds to GnRH receptors in the pituitary, suppressing LH and FSH secretion in a dose-dependent manner. The suppression of LH begins approximately 2 hours after administration of a 0.25 mg dose and is maintained with continuous treatment. Its inhibitory effect on LH is more pronounced than on FSH. No initial stimulation of gonadotropin release is observed, consistent with its antagonist profile.

The inhibitory effects on LH and FSH are reversible after discontinuation. In women, Cetrorelix delays the LH surge and ovulation in a dose-dependent manner without significantly affecting FSH levels during controlled ovarian stimulation. A daily dose of 0.25 mg has been shown to effectively maintain suppression.

Cetrorelix Acetate administered subcutaneously once daily (0.25 mg dose) at 24 hour intervals, either in the morning or in the evening as part of the multiple dose protocol during the early-to mid-follicular phase (Day 5/6 to Day11). It is for subcutaneous injection into the lower abdominal wall. The first administration of Cetrorelix Acetate 0.25 mg should be performed under the supervision of a physician. The reconstituted product is to be administered subcutaneously. Use immediately after reconstitution.

Choose an injection site on your lower abdominal area. It should be preferably around, but at least one inch away, from your belly button. Choose a different injection site each day to minimize local irritation. Take the second alcohol wipe, clean the skin at the injection site and allow the alcohol to dry. Keep the alcohol wipe nearby.

Pick up the syringe. Invert the syringe and hold it as if throwing a dart. With your other hand, gently squeeze the skin together to make a little elevation at the injection site. Using a 'dart like motion', slowly insert the needle at an angle of about 45° to 90° (you need very little force but quick action).

Once the needle is inserted into the tissue all the way, inject the solution. Do this by pushing gently on the plunger with your thumb of the hand holding the syringe. Take as much time as you need to inject all the solution.

Immediately withdraw the needle. Clean the injection site with the clean side of the alcohol pad using a circular motion. If there is minor oozing, you may need to apply a small amount of pressure for a minute.

Use the syringe and needles only once. Dispose of the syringe and needles immediately after use. Discard into a disposal container or puncture-proof container with a lid that fits firmly.

• Known hypersensitivity to cetrorelix acetate, peptide hormones, or mannitol
• Pregnancy and lactation
• Postmenopausal women
• Patients with moderate to severe renal or hepatic impairment

The most frequently reported adverse effects include local reactions at the injection site such as redness, swelling, and itching, which are usually mild and temporary. Mild to moderate ovarian hyperstimulation syndrome (OHSS) (WHO grade I or II) may also occur and is considered an inherent risk of ovarian stimulation therapy.

Cetrorelix Acetate should not be used during pregnancy or breastfeeding.

• Allow the medication to reach room temperature before injection; remove it from refrigeration about 30 minutes prior to use
• Do not use if the reconstituted solution appears cloudy or contains particles
• Use the solution immediately after reconstitution

In case of suspected overdose, seek immediate medical attention from a healthcare provider, hospital emergency department, or poison control center, even if no symptoms are present.

Drugs affecting (inhibiting) gonadotropin

Use immediately after reconstitution. Store in a refrigerator at 2°C to 8°C. Do not freeze. Protect from light and moisture. Keep out of reach of children.