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Medically reviewed by Last updated on Jul 24, 2020.


(ga ni REL ix)

Index Terms

  • Antagon
  • Ganirelix Acetate

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Solution Prefilled Syringe, Subcutaneous, as acetate:

Generic: 250 mcg/0.5 mL (0.5 mL)

Pharmacologic Category

  • Gonadotropin Releasing Hormone Antagonist


Competitively blocks the gonadotropin-release hormone receptors on the pituitary gonadotroph and transduction pathway. This suppresses gonadotropin secretion and luteinizing hormone secretion preventing ovulation until the follicles are of adequate size.


SubQ: Rapid


Mean Vd: Single dose: 43.7 L; Multiple dosing: 76.5 L


Hepatic to two primary metabolites (1-4 and 1-6 peptide)


Feces (75%) within 288 hours; urine (22%) within 24 hours

Time to Peak

1.1 hours

Duration of Action

<48 hours

Half-Life Elimination

Single dose: 12.8 hours; Multiple dosing: 16.2 hours

Protein Binding


Use: Labeled Indications

Adjunct to controlled ovarian hyperstimulation: Inhibits premature luteinizing hormone (LH) surges in women undergoing controlled ovarian hyperstimulation.


Hypersensitivity to ganirelix or any component of the formulation; hypersensitivity to gonadotropin-releasing hormone (GnRH) or any other GnRH analog; known or suspected pregnancy

Canadian labeling: Additional contraindications (not in US labeling): Moderate or severe renal impairment; moderate or severe hepatic impairment

Dosing: Adult

Adjunct to controlled ovarian hyperstimulation: SubQ: 250 mcg once daily during the mid-to-late phase after initiating follicle-stimulating hormone on day 2 or 3 of cycle. Treatment should be continued daily until the day of chorionic gonadotropin administration.

Dosing: Geriatric

Refer to adult dosing.


SubQ: Administer SubQ in abdomen (around navel) or upper thigh; rotate injection site.


Store at 25°C (77°F); excursions are permitted between 15°C and 30°C (59°F and 86°F). Protect from light.

Drug Interactions

Indium 111 Capromab Pendetide: Antigonadotropic Agents may diminish the diagnostic effect of Indium 111 Capromab Pendetide. Avoid combination

Adverse Reactions

The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified.

1% to 10%:

Central nervous system: Headache (3%)

Endocrine & metabolic: Ovarian hyperstimulation syndrome (2%)

Gastrointestinal: Abdominal pain (1%), nausea (1%)

Genitourinary: Pelvic pain (5%), vaginal hemorrhage (2%)

Local: Injection site reaction (1%)

<1%, postmarketing, and/or case reports: Anaphylactoid reaction, hypersensitivity reaction


Concerns related to adverse effects:

• Hypersensitivity: Hypersensitivity reactions, including anaphylactoid reactions, have been reported; may occur with the first dose; use is not recommended in women with severe allergic conditions. Use with caution in women with signs and symptoms of other allergic conditions.

Special populations:

• Pregnancy: Exclude pregnancy before beginning treatment.

Dosage form specific issues:

• Latex: The packaging may contain natural rubber latex.

Other warnings/precautions:

• Experienced specialists: Should only be prescribed by fertility specialists.

Monitoring Parameters

Ultrasound to assess follicle size

Reproductive Considerations

Ganirelix is used to treat infertility; pregnancy should be excluded prior to treatment.

Pregnancy Considerations

Ganirelix is used to treat infertility; use is contraindicated in women who are already pregnant.

Studies in animals have shown evidence of fetal abnormalities, including fetal resorption. Fetal resorption is a result of hormonal alterations and could result in fetal loss in humans.

Patient Education

What is this drug used for?

• It is used to help women get pregnant.

• It may be given to you for other reasons. Talk with the doctor.

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Injection site irritation

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Severe vaginal bleeding

• Ovarian hyperstimulation syndrome like severe abdominal pain or bloating; severe nausea, vomiting, or diarrhea; excessive weight gain; shortness of breath; or change in how much urine is passed

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a limited summary of general information about the medicine's uses from the patient education leaflet and is not intended to be comprehensive. This limited summary does NOT include all information available about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not intended to provide medical advice, diagnosis or treatment and does not replace information you receive from the healthcare provider. For a more detailed summary of information about the risks and benefits of using this medicine, please speak with your healthcare provider and review the entire patient education leaflet.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.