Drug reference

Ganirelix

Gonadotropin-releasing hormone (GnRH) antagonist (decapeptide) · Gonadotrophin-affecting drug for infertility and controlled ovarian stimulation

Also known as ANTAGON

START

0.25 mg SC once daily from day 5–6 of FSH stim; continue to hCG trigger

TYPICAL MAX

0.25 mg SC once daily

STOP IF

Anaphylaxis or established pregnancy

WATCH

Pregnancy confirmation; LH/oestradiol; OHSS monitoring

CDSCO approvedSchedule HATC H01CC01

Renal dose adjustmenteGFR mL/min/1.73m²

KDIGO 2024 + manufacturer label

Pharmacokineticsplasma · t hours

ONSET: 1h · SC absorption
PEAK: 1.5h · Tmax
t½: 16h · t½
DURATION: 1d · once-daily

EXCRETION

Faecal and renal — metabolites

route + CYP

INTERACTIONS

1 major

SEVERE in our sources

PREGNANCY

Contraindicated — fetal harm if dosing continues after conception.

FDA category + note

Top interactionssee all 5 →

Gnrh AgonistsSevereDatabaseKimi deep-research + Cla

Mechanism

Synthetic decapeptide that competitively blocks pituitary GnRH receptors, suppressing LH and FSH release immediately — used to prevent premature LH surge during controlled ovarian hyperstimulation in ART.

Indications

Inhibition of premature LH surge in women undergoing controlled ovarian hyperstimulation (in-vitro fertilisation)

Dosing

Adult: 0.25 mg SC once daily starting on day 5 or 6 of FSH stimulation; continue until day of hCG trigger.
Pediatric: Not applicable.
Renal adjustment: Avoid in severe impairment (limited data).
Hepatic adjustment: No adjustment.
Geriatric: Not applicable (reproductive-age use).
Max dose: 0.25 mg SC once daily

Pharmacokinetics

Onset

LH suppression within hours

Peak effect

~1–2 h (SC Tmax)

Duration

~24 h (once-daily)

Half-life

~16 h

Bioavailability

~91% (SC)

Protein binding

~82%

Metabolism

Peptidase hydrolysis

Excretion

Faecal and renal (metabolites)

Contraindications

Pregnancy
Hypersensitivity to ganirelix or GnRH analogues
Severe renal impairment

Side effects

Common

Injection-site reactionsHeadacheNauseaPelvic / abdominal pain

Serious

Severe hypersensitivity (rare, anaphylaxis)
Ovarian hyperstimulation syndrome (background ART risk)
Fetal harm if used in established pregnancy

Pregnancy & lactation

Pregnancy

Contraindicated — fetal harm if dosing continues after conception.

Lactation

Avoid (limited data).

Drug interactions

Gnrh Agonists

Severe

Database

Pharmacologic antagonism

Do not co-administer in same cycle