To prevent double administration of drugs by letting a patient determine his family pharmacy.

A drug administration system includes a reception agency 1 with a means for performing the process of receiving a prescription P issued to each patient; an intelligence agency 4 with a means for storing into a database 41 information on administration to each patient according to information on the prescription P received by the reception agency 1; a preparation agency 2 with a means for outputting drug preparation instructions according to the information on the prescription P received by the reception agency 1; and an administration agency 3 with a means for outputting instructions whereby the drug prepared and delivered according to the instructions output by the preparation agency 2 is administered according to the information on the administration to each patient that is accumulated in the database 41.