(redirected from Antagon)


a synthetic compound derived from, and an antagonist to, gonadotropin-releasing hormone; used as the acetate salt to inhibit premature luteinizing hormone (LH) surges in women undergoing ovarian hyperstimulation in the treatment of female infertility, administered subcutaneously.


(ga-ni-rell-ix) ,


(trade name)


Therapeutic: hormones
Pregnancy Category: X


As a component of infertility regimens (with recombinant follicle stimulating hormone [FSH], and human chorionic gonadotropin) to inhibit premature luteinizing hormone (LH) surges in patients undergoing controlled ovarian hyperstimulation.


Induces a rapid, reversible suppression of gonadotropin (FSH and LH) secretion, which suppresses surges in LH. Ganirelix is a gonadotropin-releasing hormone antagonist.

Therapeutic effects

Suppression of LH surges increases the implantation and pregnancy rates in patients undergoing in vitro fertilization.


Absorption: Well absorbed following subcutaneous administration.
Distribution: 44 L.
Metabolism and Excretion: Metabolized to two primary metabolites; 18% excreted unchanged in urine.
Half-life: 16 hr.

Time/action profile (blood levels)

Subcutunknown1 hrunknown


Contraindicated in: Hypersensitivity to ganirelix, gonadotropin releasing hormone or any of its analogs; Obstetric: Known or suspected pregnancy.
Use Cautiously in: None noted.

Adverse Reactions/Side Effects


  • ovarian hyperstimulation syndrome (life-threatening)
  • abdominal pain
  • nausea


  • pelvic pain
  • vaginal bleeding


  • hypersensitivity reactions (life-threatening)
  • injection site reactions


Drug-Drug interaction



Subcutaneous (Adults) 250 mcg once daily during the mid-to-late follicular phase of menstrual cycle after initiating FSH on day 2 or 3 of cycle. Treatment with ganirelix should be continue daily until day of administration of human chorionic gonadotropin (when adequate follicular response achieved).


Injection: 250 mcg/0.5 mL in prefilled syringes

Nursing implications

Nursing assessment

  • Assess patient for pregnancy prior to therapy. Therapy should not be initiated if patient is pregnant.
  • Lab Test Considerations: May cause elevated neutrophil counts and decreased hematocrit and total bilirubin concentrations.

Potential Nursing Diagnoses

Deficient knowledge, related to medication regimen (Patient/Family Teaching)


  • Subcutaneous: Administer via subcutaneous injection only.

Patient/Family Teaching

  • Instruct patient on correct technique for subcutaneous injection. Most convenient sites are in the abdomen around the navel and in the upper thigh.

Evaluation/Desired Outcomes

  • Successful in vitro fertilization procedure.


/gan·i·re·lix/ (gan″ĭ-rel´iks) a synthetic decapeptide derived from, and an antagonist to, gonadotropin-releasing hormone; used as the acetate salt in the treatment of female infertility.


a gonadotropin-releasing hormone antagonist.
indications It is used to inhibit premature luteinizing hormone surges in women undergoing controlled ovarian hyperstimulation.
contraindications Pregnancy, lactation, latex allergy, and known hypersensitivity to this drug prohibit its use.
adverse effects Fetal death is a life-threatening consequence of this drug's use. Other adverse effects include headache, ovarian hyperstimulation syndrome, gynecological abdominal pain, nausea, and pain on injection. Common side effects include spotting and breakthrough bleeding.
References in periodicals archive ?
The Stockton extravaganza builds to a huge crescendo as Antagon Theatre with Meridians climax events tonight (from 9.
Food and Drug Administration's approval of ANTAGON (ganirelix acetate) Injection, indicated for inhibiting premature leutenizing hormone (LH) surges in women undergoing controlled ovarian hyperstimulation.
ANTAGON, which will be available by prescription later this year, can be self-administered by the patient via a subcutaneous injection, and clinical tests have shown that it is extremely well-tolerated.
CHAPTER 5 METHODS OF TREATMENT 63 FERTILITY PHARMACEUTICALS 63 INTRODUCTION AND TYPES 63 Antagon 64 Bravelle 65 Cetrotide 65 Clomid 65 Crinone and Prometrium 66 Fertinex 67 Follistim 67 Gonal-F 67 Humegon 68 Lupron 68 Novarel 68 Ovidrel 69 Parlodel 69 Pregnyl 69 Profasi 69 Prometrium 69 Repronex 69 Serophene 70 TABLE 8 SELECTED PRESCRIPTION FERTILITY DRUGS 70 MARKET REVENUES AND FORECAST 71 TABLE 9 MARKET SIZE OF GLOBAL INFERTILITY PHARMACEUTICALS AT U.
Themed around water, Antagon Theatre discovers the past of the European continent and its countries, through music, interpretative dance, stilt-work and acrobatics.
ANTAGON is the first gonadotropin-releasing-hormone (GnRH) antagonist approved for this indication in the USA.
Antagon Theatre return with a specially commissioned performance, Remember the Future.
The antagonist group received an evening dose of 250 micrograms/day of Antagon when the lead follicle reached an average diameter of 12 to 14 mm.
The study compared the clinical and endocrine outcomes of in vitro fertilization (IVF) patients undergoing treatments with recombinant follicle stimulating hormone (rFSH) and a gonadotropin-releasing hormone (GnRH) analog, either the GnRH agonist, Lupron(R) (leuprolide acetate) or the GnRH antagonist, Antagon.
Directed by Antagon Theatre from Germany, it features additional performers from the North-east and Slovenia, and carries a powerful ecological message.
It's directed by Antagon Theatre from Germany with additional performers from the North-east of England and Slovenia, and carries a powerful ecological message that will resonate with young audiences.