Phenytoin enhances the rate of estrogen metabolism, which can decrease the effectiveness of some birth control pills. Options 1, 2, and 4 are inappropriate instructions. Pregnancy does not need to be â€œavoidedâ€? while taking phenytoin; however, because phenytoin may cause some risk to the fetus (Pregnancy Category D medication), consultation with the health care provider should be done if pregnancy is considered. Telling a client that there is an increased risk of thrombophlebitis is incorrect and inappropriate and could cause anxiety in the client. Aclient should not be instructed to stop antiseizure medication.