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Antagon (Subcutaneous)

Generic name: ganirelixga-ni-REL-ix ]
Drug class: Gonadotropin-releasing hormone antagonists

Medically reviewed by Drugs.com. Last updated on Nov 9, 2024.

Uses for Antagon

Ganirelix injection is used as a fertility medicine to prevent premature luteinizing hormone (LH) surges or ovulation in women undergoing fertility treatment of controlled ovarian hyperstimulation. It may also help reduce the need for follicle-stimulating hormone (FSH), which is also needed for ovulation. Ganirelix is a gonadotropin-releasing hormone (GnRH) antagonist.

This medicine is available only with your doctor's prescription.

Before using Antagon

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

No information is available on the relationship of age to the effects of ganirelix injection in the pediatric population. Safety and efficacy have not been established.

Geriatric

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of ganirelix injection in the elderly.

Breast Feeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Interactions with Medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Proper use of Antagon

A nurse or other trained health professional may give you this medicine. You may also be taught how to give your medicine at home. It is given as a shot under your skin of your stomach or thigh.

Each package of the medicine contains patient instructions. Read and follow the instructions carefully. Ask your doctor if you have any questions.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

Missed Dose

Call your doctor or pharmacist for instructions.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Do not keep outdated medicine or medicine no longer needed.

Throw away used needles and syringes in a hard, closed container that the needles cannot poke through. Keep this container away from children and pets.

Sprintec, Estarylla, Ortho Tri-Cyclen, ethinyl estradiol / norgestimate, Tri-Sprintec

Precautions while using Antagon

It is very important that your doctor check your progress often at regular visits to make sure that the medicine is working properly and to check for unwanted effects. Your doctor will probably want to follow the developing eggs inside the ovaries by doing an ultrasound examination and measuring hormones in your blood stream.

This medicine may cause serious allergic reactions, including anaphylaxis and angioedema, which can be life-threatening and require immediate medical attention. Call your doctor right away if you have a rash, itching, hoarseness, large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs, trouble breathing, trouble swallowing, or any swelling of your hands, face, or mouth while you are using this medicine.

The needle cover of the prefilled syringe contains dry natural rubber (a derivative of latex), which may cause allergic reactions in people who are sensitive to latex. Tell your doctor if you have a latex allergy before you start using this medicine.

Side Effects of Antagon

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

Less common

Rare

Incidence not known

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Commonly used brand name(s)

In the U.S.

Available Dosage Forms:

Therapeutic Class: Endocrine-Metabolic Agent

Pharmacologic Class: Luteinizing Hormone Releasing Hormone Antagonist

Further information

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