A system and method for rapid entry of past medical diagnoses allows for development of specific, clinically relevant diagnoses from a simple input medication through use of a developed database that maps an input medication to a specific medical diagnosis through an intermediate indications data set. Input medications are normalized to their generic or chemical name and the normalized medication data is associated to an intermediate diagnosis through a medications indications listing contained in a database. Each medication develops a short list of possible specific and/or macro-diagnoses (indications) consistent with the medications and a selected indication is concept-matched to a specific medical diagnosis in order to develop a proper diagnosis in clinically meaningful terms, from a concept-mapped portion of the database. The concept-mapped portion is developed by grouping medical terms into clinically meaningful groups and developing pointers within those groups between identified diseases and a developed indications taxonomy, itself developed by forming a composite of FDA-approved and non-FDA approved indications with respect to particular normalized medications.