Can plan b still be effective after 60 hours of unprotected sex?

Sure, it can be: Plan B works most of the time but not all of the time. One should do a home urine pregnancy test 3 weeks after Plan B. Also, use reliable forms of birth control so that Plan B will rarely be needed (hopefully never) in the future. Plan B is for real emergencies. A woman might need Plan B 2 or 3 times in her lifetime. That's about as many sexual emergencies a woman can expect in one lifetime.