Pharmacists Help Patients Manage Insulin Pumps for Type 2 Diabetes | ASHP Midyear 2025

The landscape of type 2 diabetes (T2D) management is rapidly evolving, shifting from traditional pharmacotherapy toward advanced device technology.

“The challenge, though, is that type 2 diabetes is a progressive condition. The longer someone has been living with it, the more likely their beta cells are not going to be able to produce enough insulin, and they may need insulin.” Diana Isaacs, PharmD, BCACP, BC-ADM, BCPS, CDCES, FADCES, FCCP, endocrine clinical pharmacy specialist at the Cleveland Clinic Diabetes Center, said in a session at the American Society for Health-System Pharmacists Midyear Clinical Meeting and Exhibition 2025. In the session, Isaacs was joined by Taylor Thooft, PharmD, BCPS, pharmacist clinician at Essentia Health.

Despite utilizing multiple daily injections (MDI), a significant portion of these patients continue to struggle, with 85% of those on MDI having an A_1C over 7%, Isaacs said. Insulin often has a narrow therapeutic window, which could make it difficult for patients and cause either hyper- or hypoglycemia.

Automated insulin delivery (AID) systems, which integrate insulin pumps with continuous glucose monitors (CGMs), are a potential solution. These systems are designed to provide a more physiologic insulin release pattern compared to injections, ultimately helping to improve glycemic outcomes and reduce the risk of hypoglycemia. Given the complexity and clinical necessity of these devices, pharmacists, particularly those specializing in endocrinology, are essential in driving the adoption of AID.

Redefining the Ideal Pump Candidate

The American Diabetes Association Standards of Care recommend that diabetes devices should be offered to people with diabetes, Isaacs noted. Specifically, insulin pump therapy, preferably integrated with CGMs, should be offered to youth and adults on MDI for T2D as a Level A recommendation.

“We've completely shifted because what we've realized is that this technology is too good,” Isaacs said. "The outcomes are too good that it's not right if we deny people the right to use this technology based on what we think they can handle."

Isaacs noted that previous attitudes suggested patients had to "earn their right" to a pump by demonstrating excellent control and expert carbohydrate counting, among other checklist items that created disparities. High A_1C levels, often seen as a barrier, may actually indicate the patients who stand to benefit the most from AID. The choice of device, in all cases, should be based on the individual's circumstances, preferences, and needs.

Ideal candidates must require mealtime insulin to reach their glycemic targets and must be willing to follow up with the care team. Because transitioning off long-acting insulin poses a risk of diabetic ketoacidosis if pump delivery is interrupted, patients—or their caregivers—must possess problem-solving skills to recognize and correct issues like kinked tubing, the device falling off, or refilling as needed. Although patients do not need to be expert carbohydrate counters, an awareness of carbohydrate consumption is necessary for appropriate meal bolusing, which will be used for AID pumps. Finally, patients must be able to afford the ongoing supplies and must maintain a backup plan in case of device failure or supply shortages.

The Pharmacist's Role in Calculating Settings

Pharmacists are involved in helping to identify patients who might benefit from these therapies, as well as helping with the patient’s initial pump settings. Insulin pumps use a single type of rapid-acting U-100 insulin for both basal and bolus needs. This single insulin type is in and out of the system more quickly than traditional long-acting injection insulin, making dosing highly precise.

The process begins with a pharmacist calculating the patient's total daily insulin (TDI), which is the sum of their current long-acting and mealtime insulin doses. Because pump delivery is more effective unit-per-unit, the initial pump TDI is typically reduced, often by 25%, or calculated by averaging the reduced current dose with a weight-based dose to ensure a safer and more effective starting point. Pharmacists use standardized rules to estimate the specific programmable settings.

The insulin-to-carbohydrate ratio determines how many grams of carbohydrates 1 unit of insulin covers, which Isaacs said pharmacists can use the Rule of 450 divided by the pump TDI. The correction factor, which determines how many points 1 unit of insulin is expected to lower glucose, is calculated using the Rule of 1700 divided by the pump TDI. The 1700 rule is commonly used in pumps instead of the 1800 rule because the resulting calculation is slightly more aggressive, which generally enhances pump performance, Isaacs noted.

Optimizing Therapy through Data Review

Ongoing management requires pharmacists to regularly review data reports, such as those provided by Glooko or CareLink, to monitor adherence and fine-tune therapy. The first area of focus should always be the percentage of time the patient is in automated mode, as low adherence to automation requires investigation since automated mode generally yields better outcomes. In highly automated systems like the MiniMed 780G, optimization often involves adjusting a few key parameters. For instance, the glucose target may be lowered, or the active insulin time can be adjusted to intensify therapy.

Additionally, patient education on bolus timing is critical. Although patients should pre-bolus for meals, human behavior is often imperfect. Pharmacists must counsel patients that if they bolus late (such as 30 to 60 minutes after eating), they should enter only half the carbohydrate amount, or if they are more than 60 minutes late, they should only deliver a correction dose based on their current glucose level to avoid dangerous hypoglycemia caused by background insulin ramping up.

“If they put in their full amount of carbs and it's an hour later, they could end up getting too much and going low,” Isaacs said. “If it's been beyond 60 minutes, just give a correction dose at that point using the current glucose level."

Conclusion

Beyond clinical management, pharmacists must also navigate the logistical side of AID therapy. When dispensing insulin, they often need to slightly inflate the calculated TDI amount when submitting prescriptions to insurance. This inflation ensures the patient receives enough insulin supply to cover both their daily needs and the additional volume required for automated adjustments and correction boluses.

The transition to pump therapy for T2D requires comprehensive engagement from pharmacists. By maintaining proficiency in device settings, calculation rules, and system differentiation, pharmacists ensure that more patients have access to this vital technology tailored to their specific needs and circumstances.

"The problem is that, with insulin, it's a tough drug. It's got a narrow therapeutic window, and it's actually very challenging to deliver insulin and not have too much hypoglycemia or hyperglycemia,” Isaacs said. “There's a lot of data to support that insulin pumps really help people with their insulin delivery and improve outcomes like A_1C and other outcomes."

REFERENCE

Isaacs D, Thooft T. Ante Up for Innovation: Insulin Pumps for Type 2 Diabetes. ASHP Midyear Clinical Meeting and Exhibition 2025. December 7-10, 2025. Las Vegas, Nevada.