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What is ganirelix?


Ganirelix (brand name Antagon« is no longer available) is a gonadotropin-releasing hormone (GnRH) antagonist drug that can be used in the treatment of infertility. Infertility is described as the inability to conceive a baby within one year of trying. Ganirelix is a synthetic (man-made) hormone that inhibits early luteinizing hormone (LH) surges in females undergoing a fertility procedure called ovarian hyperstimulation. An LH surge normally causes ovulation (release of the egg), but it is stopped by ganirelix until the conditions are right for the fertilization procedure to begin. The dose of injectable ganirelix varies from person to person and may be given at a clinic or at home. Talk to your doctor about the best dose for you. Because it is often given with other fertility medications, it is important to discuss the timing of doses with your doctor.

Side Effects

Side effects of ganirelix include injection site redness, itching, swelling, pain, headache, vaginal bleeding, ovarian hyperstimulation syndrome and nausea. In a small percentage of cases, fetal death has occurred. Notify your doctor immediately if you experience severe abdominal pain, nausea and vomiting, and rapid weight gain. If you are having difficulty becoming pregnant, be sure to talk to your doctor about what the best treatment is for you.

Learn about hormone levels in our Health Encyclopedia.

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