The duration of the 3 mg single dose is four days; if human chorionic gonadotropin (hCG) is not administered within four days, a daily 0.25 mg dose is started and continued until hCG is administered.
A 3 mg dose lasts for four days; if hCG is not given within this timeframe, a 0.25 mg dose is begun daily and continued until hCG is administered.