Cetrotide (cetrorelix for injection) is a fertility medication that contains cetrorelix acetate. It works by blocking the effect of a natural hormone called “gonadotropin-releasing hormone” (GnRH). GnRH controls the release of another hormone involved in ovulation, called luteinizing hormone (LH). LH starts ovulation (the release of an egg) during your menstrual cycle.

Cetrotide stops the body from releasing an egg from the ovary (ovulation). It controls ovulation so that it happens at the best time for you to become pregnant. It is used in assisted reproductive techniques to help women (patients with ovaries) get pregnant.

Cetrotide is supplied in a single-dose vial. Cetrotide comes in a packaged tray containing:

• One glass vial with 0.25 mg cetrorelix
• One pre-filled glass syringe with 1 mL of Sterile Water for Injection
• One 20-gauge needle (yellow) used for mixing
• One 27-gauge needle (grey) used for injection

• Store between 2-8°C (in the refrigerator)
• • Storage at up to 30°C for a maximum of 3 months is allowed
• Do not freeze
• Store in a cool and dry place, and protect from excess moisture and heat
• Keep the container in the outer carton in order to protect it from light
• Keep in a safe place out of the reach of children
• Do not use after the expiry date
• The solution should be used immediately after preparation

Dispose of used needles and syringes immediately after use into a sharps disposal container. This container is usually provided by your clinic or pharmacy. Use the syringe and needles only once.

Cetrotide is given by subcutaneous injection (just under the skin). Your doctor or nurse should supervise your first injection and show you how to inject Cetrotide. After this, you can inject Cetrotide on your own in the comfort and privacy of your own home.

Cetrotide is injected in your lower abdominal area. Preferably, you should inject around − but at least one inch away from − your belly button. Choose a different injection site each day to minimize irritation.

Shaded area shows recommended injection site

Contact your clinic for advice if you forget to take a dose of Cetrotide. Do not take a double dose to make up for any doses you have missed.

If you have accidentally injected too much Cetrotide, contact your clinic or another healthcare professional, hospital emergency department, or regional poison control centre immediately, even if there are no symptoms.

Do not use Cetrotide if you:

• Are allergic to cetrorelix or mannitol, which are ingredients in Cetrotide
• Are allergic to any component of the Cetrotide container
• Are allergic to medicines called peptide hormones
• Are allergic to a hormone called gonadotropin-releasing hormone (GnRH) or to medicines called GnRH analogs  
• Are pregnant, think you might be pregnant, or are breastfeeding (feeding a baby your own milk)
• Have moderate or severe liver or kidney problems

To help avoid side effects and ensure proper use, talk to your doctor or pharmacist before you take Cetrotide. Tell your doctor about any health conditions or problems you may have, including if you:

• Are taking or have recently taken other medicines, including those not requiring a prescription
• Have an active allergy
• Have had allergies in the past

Other warnings you should know about:

• Using Cetrotide during more than one cycle: Your doctor will carefully look at the benefits and risks for you if you need to use it during more than one cycle.
• Ovarian hyperstimulation syndrome (OHSS): With this syndrome, the ovaries become enlarged and there may be abdominal bloating and pain. Although uncommon, it can be severe and life-threatening. 
• Congenital abnormalities and stillbirths: Birth defects may be slightly more common in babies conceived by assisted reproductive technologies than in those conceived naturally. 

Refer to the Cetrotide package insert for more information about these warnings.

As with all medications, there may be side effects with Cetrotide. Side effects include:

• Headache
• Bruising, itching, swelling, pain, or redness in your abdomen where you injected Cetrotide
• Feeling sick (nausea)

This is not a complete list of side effects. Refer to the package insert for more information about possible side effects with Cetrotide, including serious side effects. 

If you experience a troublesome side effect that is not listed in the package insert or one that becomes bad enough to interfere with your daily activities, talk to your doctor.

No formal drug interaction studies have been done with Cetrotide. Nevertheless, it’s a good idea to tell your doctor about all the medicines you take, including any drugs, vitamins, minerals, natural supplements, or alternative medicines.