Andrew Almon Fletcher
Andrew Almon Fletcher (March 8, 1889 – November 30, 1964) was a Canadian doctor who helped pioneer diabetes treatment. He was one of five co-authors of the 1922 paper Pancreatic Extracts in the Treatment of Diabetes Mellitus.
Education and career: Fletcher earned an M.B. from the University of Toronto in 1913. He served overseas with the Canadian Army Medical Corps from 1915 to 1918. After World War I, he joined the University of Toronto’s Department of Medicine and the medical service at Toronto General Hospital. He qualified as F.R.C.P.C. in 1930.
From 1922 to 1951 he was an assistant professor at the University of Toronto and a senior physician at Toronto General Hospital. In 1951 he became head of the clinical investigation unit at Sunnybrook Military Hospital in Toronto, which later became Sunnybrook Health Sciences Centre.
Work in diabetes care: In Toronto General Hospital’s diabetes ward, under Duncan Archibald Graham, Fletcher and Walter R. Campbell treated Leonard Thompson, a teenage patient with very severe Type 1 diabetes. Thompson had been moved from the Hospital for Sick Children on December 2, 1921. Campbell persuaded Thompson’s father to allow testing of a pancreatic extract provided by Banting, Best, and Macleod. The first insulin injection was given on January 11, 1922.
Awards: In 1953 Fletcher and Campbell received Banting Medals from the American Diabetes Association.
Personal life: He married Helen Waterston Mowat on September 21, 1921; she was the granddaughter of Sir Oliver Mowat. They had four daughters. Fletcher is buried at Mount Pleasant Cemetery in Toronto.
This page was last edited on 2 February 2026, at 18:51 (CET).