The amount of insulin required to produce coma during the course of insulin shock therapy (IST) by the rapid induction method (Bond and Shurley1) is not constant but is considerably reduced after the first coma. We have previously observed (Dohan and associates2) that the mean lowest coma dose usually occurs in the fourth or fifth week of therapy and is approximately one-fourth or less of that required to produce the initial coma. Hypothetically, the most probable factors responsible for this change in "insulin sensitivity" might be (a) that a smaller dose of insulin causes an approximately equal or greater fall in true blood glucose or (b) that the central nervous system is "sensitized" with development of stupor or coma at greater blood glucose concentrations. This study was designed to test these possibilities.
We have published data2 suggesting that repeated insulin shock is associated with decreased basal function
BENNETT IF, LETONOFF TV, WINICK W, DOHAN FC. Relationship of Blood Glucose to Changes in "Insulin Sensitivity" During Insulin Shock Therapy. AMA Arch NeurPsych. 1957;78(3):221-227. doi:10.1001/archneurpsyc.1957.02330390003001