There is no medical reason why you can't use Levonelle One Step® as often as necessary, but you should try not to take it more than once in any one cycle as there is a greater likelihood that Levonelle One Step® will disrupt the timing of your next period. Nor should you use it as a regular method of contraception because on it's own, it is not as reliable as regular, long-term methods of birth control and you would increase your chances of an unplanned pregnancy.