can postinor 2 work after four days of intercourse?

a friend of my had sex with her guy on Sunday night and wat to take postinor 2 on Wednesday morning will it work

Hello Anonymous,

Welcome to EmpowHER and thank you for reaching out to us with your question.

Postinor 2 is 95% effective in preventing pregnancy if taken within 72 hours or 3 days following unprotected intercourse or contraceptive failure. The sooner it is taken, the more effective it is.
But, I don't think it would be effective and worth taking now that four days have passed.

When was your girlfriend's period due to start? Postinor 2 prevents pregnancy by preventing ovulation. If this happened around the time of ovulation, which is about 14 days following the last day of her last period, or five days before ovulation, there is a good chance she did become pregnant.

If her periods are regular, and this month's period is late by at least seven days, she should take a home pregnancy test. For the most accurate result, please purchase a name brand product, check the expiration date, read and follow the directions carefully, and most important of all, she must test in the morning and use the first urine of the day.

Regards,
Maryann