January 11: The first use of insulin to treat diabetes in a human patient (1922)

Insulin vial

Leonard Thompson, a 14 year-old diabetes patient, was given the first injection of insulin by Dr. John Macleod at the Toronto General Hospital on January 11, 1922. Dr. Macleod invited the biochemist James Collip to purify the extracted insulin from fetal calf pancreas. After the first injection, Thompson suffered a severe allergic reaction and the further injections were cancelled. Collip worked for improving the ox-pancreas extract over the next 12 days. The second inject was given to Thompson on January 23 and it was a complete success without any side effect and it eliminated the glycosuria sign of diabetes. It was a significant breakthrough to the cure of diabetes.