The Physicians’ Desk Reference (PDR) is a commercially published compilation of manufacturers’ prescribing information (package insert) on prescription drugs, updated annually. While designed to provide physicians with the full legally mandated information relevant to writing prescriptions (just as its name suggests), it is widely available in libraries and bookstores, widely used by other medical specialists, and in significant part valuable to consumers. It is financially supported in part by pharmaceutical manufacturing corporations which create drugs listed within its pages.

Since the late 20th century, a consumer edition has been offered at a much reduced price. Electronic editions are available on CD-ROM and the World Wide Web to subscribers. PDR is owned by the Thomson Corporation of Toronto. In 1984, Paul C. Kranz and Michael Grondin travelled to Oradell, New Jersey, and presented to Medical Economics (then-publisher of the PDR) a prototype developed by Grondin on a TI 99/4A computer of how a digital copy of the PDR would work and benefit clinicians. The idea originally conceived by Kranz was well-received by the president and vice-president of IT and an agreement was struck to investigate. The result was the PDR on CD-ROM.

The main edition is usable by determined consumers in conjunction with a medical dictionary. Many practicing physicians receive free copies of the PDR and are willing to give a patient a previous year’s edition when they receive their new one but a recent edition generally differs from the current one by the absence of the drugs introduced during the course of the intervening year.