George Widmer Thorn (January 15, 1906 - June 26, 2004) was an American physician whose contributions led to new treatments of kidney diseases and adrenal gland disorders, most notably Addison's disease. Thorn was Chief of Medicine at Boston's Peter Bent Brigham Hospital, presently known as Brigham and Women's Hospital. Thorn pioneered the use of cortisone for treating Addison's disease, and devised an early test for this disease, now known as the Thorn test.His research of cortisone and ACTH led to new treatments of other diseases such as hypertension, rheumatoid arthritis and diabetes.