Jeremy A. Greene, M.D., Ph.D., is associate professor of medicine and the history of medicine and the Elizabeth Treide and A. McGehee Harvey Chair in the History of Medicine at the Johns Hopkins University School of Medicine. His most recent book is Generic: The Unbranding of Modern Medicine.  Greene is author of Prescribing by Numbers: Drugs and the Definition of Disease and coeditor of Prescribed: Writing, Filling, Using, and Abusing the Prescription in Modern America, both published by Johns Hopkins.