A pharmacy post office receives prescriptions and produces through an automated pill dispensing and packaging system, pharmacy letters that are sorted and delivered as first class or priority mail pieces. The system packages the prescription medication in carriers that are sized to fit into mail sorting machines that sort the first class or priority mail pieces by postal delivery routes. The pharmacy letters include patient mailing address information such that the pharmacy letters are then fed to the mail sorting machines and sorted along with the first class or priority mail pieces for delivery by the postal delivery persons along their customary routes. The system includes a robotic subsystem that dispenses the medication from pill canisters supplied by the drug companies and provides the pills to an automated packaging system. The packaging system feeds the pills into compartments of a carrier base or blister pack and prints on the carrier or applies as labels thereto drug identification information, mailing address information and tracking information, such as a machine readable code. The packaging system then assembles and seals the carrier, such that mailing address information is available for reading by mail sorting machines. The assembled pharmacy letters are then supplied to the mail sorting machines and included in the first class or priority delivery operations of the post office. A track and trace system may be included to provide a delivery schedule to the patient and/or prescribing doctor. The track and trace system is informed when the packaging system provides a pharmacy letter to the mail sorting machines, and the system determines if the pharmacy letter will be included in the same day postal delivery operations or in the next day operations. When a pharmacy letter is delivered by the postal delivery person, he or she scans the tracking code and transmits information back to the system, which then updates its delivery schedule to show the completed delivery.