1. A method for securely transferring medical information comprising: storing information relating to a medical prescription item on a smart card, using an encryption method which provides independent verification as to the source of the information; verifying the source of the information by the provider of the medical prescription item; modifying the stored information relating to the medical prescription item when the prescription is filled; and storing the modified information on the smart card using an encryption method that provides independent verification of the source of the modified information.