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Ganirelix Injection

What is this medication?

GANIRELIX (ga ni REL iks) prevents premature ovulation in people trying to get pregnant. It works by blocking the release of a hormone that triggers ovulation. This prevents eggs from being released too early, before they are mature. It belongs to a group of medications called GnRH blockers.

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This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

COMMON BRAND NAME(S): Antagon, Ganirelix

What should I tell my care team before I take this medication?

They need to know if you have any of these conditions:

  • Kidney disease
  • Liver disease
  • An unusual or allergic reaction to ganirelix, mannitol, latex, other medications, foods, dyes, or preservatives
  • Pregnant
  • Breast-feeding

How should I use this medication?

This medication is for injection under the skin. It is usually given in a hospital or clinic setting.

If you get this medication at home, you will be taught how to prepare and give this medication. Use exactly as directed. Take your medication at regular intervals. Do not take it more often than directed.

It is important that you put your used needles and syringes in a special sharps container. Do not put them in a trash can. If you do not have a sharps container, call your pharmacist or care team to get one.

Talk to your care team about the use of this medication in children. Special care may be needed.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

Try not to miss a dose. If you do miss a dose, call your care team for advice.

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What may interact with this medication?

Do not take this medication with any of the following:

  • Chasteberry

This medication may also interact with the following:

  • Herbal or dietary supplements, such as black cohosh or DHEA

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medication?

Visit your care team for regular checks on your progress and discuss any issues before you start taking this medication.

Your care team will need to monitor your hormone levels in your blood and use an ultrasound to check your response to treatment. Try to keep any appointments for testing. The timing of these tests in relation to taking your medication may be important.

If you have any reason to think you are pregnant, stop taking this medication at once and contact your care team.

What side effects may I notice from receiving this medication?

Side effects that you should report to your care team as soon as possible:

  • Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
  • Heavy vaginal bleeding
  • Ovarian hyperstimulation syndrome—stomach or pelvic pain, bloating, nausea, vomiting, diarrhea, weight gain

Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):

  • Headache
  • Nausea
  • Pain, redness, or irritation at injection site
  • Stomach pain

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medication?

Keep out of the reach of children and pets.

Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Protect from direct light and heat. Throw away any unused medication after the expiration date.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

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Note: Introduction and Additional Common Questions written and medically approved by Cleveland Clinic professionals.

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