Abstract: A method is provided for utilizing a history database to process a prescription drug authorization request. One embodiment, among others, comprises the steps of: searching an authorization criteria database, producing authorization category records matching a drug identifier; for each of these records, adding a history record; receiving an authorization request; searching the criteria database, producing another set of authorization category records matching the category of the drug identifier; for each of these records, formulating a key comprising the request patient identifier and the matching authorization category; querying the history database using each formulated key, producing history records; and granting or denying the request based on applying the second set of authorization category records to the history records. The history record contains a composite key combining a portion of received claim information and at least a portion of the matching authorization category record.