Morning after pill and Norethisterone

Dear Ask The Doctor: Does norethisterone affect the morning after pill ? I came of norethisterone the day before having to take the morning after pill; is there any chance the morning after pills actions could have been interfered with because of it?

Dear Bethany: It is unlikely. Norethisterone and Levonorgestrel (Plan B pill) has no drug interactions; it will not decrease the effectivity of the morning after pill. If you used Ellaone, this is a new drug and its interactions with other drugs have not been well studied. You should still continue Norethisterone. I do hope this helps and take care always.