1. A computer-implemented method of transferring information between a user and a third party through a centralized computer having a prescription medications information database, said method comprising the steps of: receiving, at the centralized computer, product identification information identifying a product from a user; storing the product identification information in said product information database and establishing a link between said product and said user; receiving, at the centralized computer, the user's dynamically changing biological variables transmitted by the user from a remote location at different points in time, the biological variables being measured by health monitoring devices; receiving, at the centralized computer, product update information on said product from a third party; updating, by the centralized computer, said product information database with said product update information, wherein new information about the product is entered into the centralized computer; reviewing, by the centralized computer, the product information database to identify user-product links associated with said product; transmitting, on an automated basis, an electronic message containing said product update information of all users identified as having user-product links; storing, in response to a user purchase of said product, product identification information for said product under a username; receiving by the centralized computer, product update information on said product; analyzing, by the centralized computer, interaction of the product with the biological variables from the user for potential harm indicated by the measured values of the biological variables and interaction with the product; identifying, by said centralized computer, a point in time from the different points in time at which the dynamically changing biological variables cause a potentially harmful interaction with the product; reviewing, by said centralized computer, the database for product identification information correlating with said product update information; identifying the username as linked with the product; and transmitting a message to said username with said product update information and a contraindication of use of the product based upon the measured biological variables at the point in time from the different points in time.