It may depend on the type of medication you are taking to treat epilepsy. Birth control pills and other contraceptive methods (the patch and the ring) that contain estrogen can speed up the metabolism of some anti-epileptic medications, such as Lamictal, due to the induction of liver enzymes. Contraceptives containing estrogen may not have the same effect if you use an anti-epileptic medication that isn't non-enzyme-inducing.