Short answer: The ganirelix label gives 250 mcg injected under the skin once daily during the mid to late follicular phase, after FSH has been started on cycle day 2 or 3, and continued daily until the day hCG is given. In the label's studies it started on day 6 of FSH, and the mean length of ganirelix treatment was 5.4 days (range 2 to 14).
This is what the FDA label says. Follow your prescriber. Your prescriber may use a different dose or pace than the label's standard schedule.
What Ganirelix is approved for: Ganirelix Acetate Injection is a GnRH antagonist approved to prevent premature LH surges (early ovulation) in women having controlled ovarian hyperstimulation (Indications and Usage). It is used alongside FSH during an IVF or ICSI stimulation cycle. This page uses Organon's label; other makers' generic ganirelix labels are separate.
Source
Ganirelix Acetate Injection 250 mcg/0.5 mL, for subcutaneous use, prescribing information. Organon. DailyMed, version published October 12, 2026. DailyMed setid 32fb74ff-993a-49fe-8943-e029372b863e
Ganirelix comes ready to use in a single-dose prefilled syringe of 250 mcg/0.5 mL with a 27 gauge, half-inch needle attached. Air bubbles in the syringe are expected and do not need to be removed (Dosage and Administration and How Supplied).
The label names the abdomen around the navel or the upper thigh as the most convenient sites, varying the site a little each time. The needle goes in at the base of pinched-up skin at 45 to 90 degrees (Dosage and Administration).
Each syringe is used only once. It is stored at 25 C (77 F), with excursions from 15 to 30 C allowed, and protected from light (Dosage and Administration and Storage).
The table below is the label's schedule, from the Dosage and Administration section. Numbers are copied exactly; the section is in brackets.
| Step | What the label says |
|---|---|
| FSH stimulation | Started on Day 2 or 3 of the cycle |
| Ganirelix dose | 250 mcg subcutaneously once daily during the mid to late portion of the follicular phase |
| Start used in the studies | Morning of cycle Day 7 or 8 (Day 6 of recombinant FSH) |
| How long | Continued daily until the day of hCG administration; mean 5.4 days (2-14) in the studies |
| Trigger | hCG when ultrasound shows a sufficient number of follicles of adequate size; withheld if the ovaries are abnormally enlarged on the last day of FSH |
Because ganirelix works with the body's own FSH, the amount of FSH given by injection may be reduced.
Steady-state levels are reached after 3 days of treatment. After ganirelix is stopped, pituitary LH and FSH levels fully recover within 48 hours.
In the dose-finding study, the 250 mcg dose gave the highest pregnancy and implantation rates of the doses tested (62.5 to 2000 mcg).
If blood is drawn into the syringe, the needle is repositioned without removing it, or a new syringe is used; the site should stop bleeding within one or two minutes with pressure.
The ganirelix label gives no missed-dose instruction. Ask your fertility team what to do if a dose is missed or late.
In Dose Track you set up Ganirelix as a protocol with the dose and schedule your prescriber gave you. A protocol can hold dose steps, each with its own dose and length in days or weeks, so a step-up plan like the one on the label can be entered once and the app moves to the next step on its own. Reminders follow the schedule, and every dose is logged with the date and time, so you can see which step you are on and when your last dose was. The app follows what you enter; it does not choose or change a dose.
This page is what the FDA label says, in plain words. It is not medical advice. Follow your prescriber, and ask them or your pharmacist about anything here.