Diabetic Ketoacidosis From Health Insurance-Requested Non-medical Switching

Non-medical switching is a change in treatment regimen for reasons other than efficacy, side effects, or adherence, with the purpose of decreasing healthcare costs. A 20-year-old female with type 1 diabetes mellitus presented with diabetic ketoacidosis. She was having issues with her health insurance and pharmacy in filling her prescriptions. Her health insurance changed its drug formulary after the New Year began. In response to the request of her health insurance, her existing insulin treatment was non-medically switched to a new rapid-acting insulin and a long-acting insulin. She was confused about what she should be taking. She took her newly prescribed non-medically switched long-acting insulin three times daily before meals in place of rapid-acting insulin, along with her previously prescribed long-acting insulin. Then, she could not fill her new non-medically switched prescription, because subscribers of the same health insurance were changed to the same insulin at the same time, triggering a drug shortage in our service area. She was admitted and stayed in the hospital for three days for treatment of diabetic ketoacidosis. After her discharge, her health insurance covered the original regimen that she was on before the non-medical switch. Non-medical switching defeated its purpose and increased healthcare spending in our case. Non-medical switching not only placed additional financial burden on our patient's health, but also jeopardized patient safety by significantly contributing to an acute complication of diabetes mellitus. Further studies that compare healthcare utilization, not just drug prices, are needed to explore if non-medical switching saves money and is cost-effective. This is the first case report in the medical literature that shows that non-medical switching can cause diabetic ketoacidosis.