What are side effects of plan b and how common is it to have an allergic reaction to it?

"Plan B": "Plan B" is usually described as oral contraceptives or the equivalent, taken the "morning after" unprotected sex. The "side effects" may mimic the onset of a menstrual period, with cramps and light staining secondary to withdrawal from the estrogen in the medication. It would be very unusual to have an allergic reaction, since estrogen and progesterone are natural hormones.

A/w Dr Berryman: Potential side effects w emergency contraception include: menstrual flow changes (spotting, bleeding, early or late period), nausea, vomiting, dizziness, fatigue, headache, breast tenderness & abdominal pain or cramps. Take pregnancy test & notify dr if your period is 7 or > days late. Also doubt that allergic reaction would be likely.