Why would you wait seven days!? Do you mean, wait seven days before having unprotected sex again? Read the package inster; it has a lot of helpful information as to what to do when you get sick while taking the pills. I don't remember exactly what it says, but there is a certain time period that once you pass, you'll be fine even if you do throw up.

I thought for a moment you mean "wait seven days before taking another pill". Obviously not! I am just not sure how many hours it takes for enough of the hormone to be absorbed for you to be totally safe; please read the package insert as I know it has the info you're looking for.