Have you shared the frustration with patients when they are changing reservoirs in their insulin pump daily due to their very high insulin requirements? Have you considered using U-500 insulin off label? Have you tried using it with success? One of our blog readers requested that this topic be addressed, so I agreed to share my experiences.
There are a number of published case studies that have reviewed the use of U-500 insulin using insulin pump therapy in patients with severe insulin resistance. The authors report individuals with elevated A1Cs and total daily insulin dose requirements over 200 u/day. Some patients were on multiple daily injections, others were already on pump therapy using rapid acting insulin. The results were remarkable, with substantial decreases in Hemoglobin A1C in all reported patients and increased patient satisfaction.
What are some issues to be aware of utilizing when considering U-500 insulin?
U-500 insulin in pump therapy is off label (it has not been FDA approved)
You MUST change the dose of insulin in the pump as U-500 insulin is FIVE TIMES more potent than U-100 insulin
There is substantial cost savings to the patient (or insurance company) utilizing U-500 insulin (reduction in cost of total insulin; fewer reservoirs, infusion set changes and tubing)
When the patient is admitted to the hospital, make sure the facility is aware of the difference in dosing if they are taken off their pump and placed on drip protocol.
In our practice, we have several patients who we have transferred to U-500 insulin. All patients have been morbidly obese, required over 300 units of insulin per day, and utilized insulin pump therapy. The transition from U-100 to U-500 insulin was seamless, with a change in dosing for basal rates, insulin to carbohydrate and insulin to sensitivity ratios derived by dividing insulin by 5 across the board.
Medicaid recently approved the use of U-500 insulin for an 19 year old patient in our practice with type 1 diabetes and insulin resistance using over 300 units per day of U-100 insulin (their criteria is a minimum of 200 units per day of U-100 prior to approval).
Insulin pump therapy for patients with type 1 and type 2 diabetes and insulin resistance is a relatively new field. With the increased incidence of obesity and morbid obesity, U-500 insulin may become a more common treatment choice. Hopefully, future clinical trials will further clarify its efficacy.
Please share your positive and/or negative experiences. This will help to provide more information for clinicians as we strive to improve blood sugars and decrease total treatment costs in this challenging population.