insulin shock therapy, form of psychiatric treatment in which patients were given increasingly large doses of insulin in order to induce hypoglycemia (low blood glucose) and coma. Insulin shock therapy was based on the notion that hypoglycemia-induced coma could basically “jolt” patients out of their psychoses. The approach was largely discredited by the 1960s and is no longer used.
The idea for insulin shock therapy was conceived in the 1920s by Polish psychiatrist Manfred Sakel, who accidentally administered too much insulin to a patient with a morphine addiction, triggering convulsions and coma in the patient. After regaining consciousness, the patient experienced an improvement in mental clarity and reduced symptoms of drug withdrawal. The incident led Sakel to conclude that insulin, given in doses sufficient to induce coma, could potentially rid patients of mental health conditions. Sakel began testing his theory in patients with schizophrenia in the late 1920s, administering the drug in doses high enough to not only induce unconsciousness but also sometimes trigger convulsions, which he considered to be beneficial in certain cases. In 1933 he published the results of his trials.
Despite a lack of scientific evidence to support the effectiveness or safety of insulin shock therapy, the treatment quickly became popular and was adopted by psychiatrists in countries worldwide, including Canada, China, Korea, the United Kingdom, and the United States. The approach introduced by Sakel, known as “Sakel’s technique,” entailed almost daily injections of insulin to induce unconsciousness that lasted an hour or longer. Patients were brought back to a waking state with an injection of glucose. This treatment pattern was repeated six days a week over the course of months and, in some instances, a year or more, with steady increases in insulin dose to produce deeper states of coma. Some patients experienced as many as 50 or 60 episodes of unconsciousness over the duration of therapy.
Patients experienced various effects during and after insulin shock therapy. Immediately following injection, patients exhibited a range of symptoms, including pallor, sweating, and restlessness, followed by deep sleep and finally coma. Patients were at high risk of hypoglycemic episodes and seizures when not receiving treatment, necessitating constant monitoring by nursing staff, and, following completion of the full course of therapy, patients were obese, owing to the effects of repeated glucose injections. Many patients also developed brain damage, which sometimes was erroneously perceived by psychiatrists as an improvement in mental condition. Treatment also sometimes resulted in death; estimates of the fatality rate of insulin shock therapy vary from 1 to nearly 5 percent.
Insulin shock therapy was considered by its proponents to be highly effective in the treatment of schizophrenia; however, in many cases schizophrenic patients were selected for therapy because they were considered to be so ill that any change in their mental state—including changes that today are considered hallmarks of brain damage—could be claimed as an improvement. By the 1950s, however, insulin shock therapy was rapidly falling out of use. The intense care necessary for patients undergoing therapy, the introduction of antipsychotic drugs, and a lack of evidence to support its effectiveness or safety were major factors in its decline.