FAQ: How Insulin Therapy Is Managed Across the Care Continuum

Insulin therapy remains one of the most effective and essential tools in the management of diabetes, yet it is also one of the most nuanced. From selecting the right formulation to navigating insurance barriers and integrating emerging technologies like continuous glucose monitors (CGMs), patients and clinicians alike face a complex and evolving landscape. Community pharmacists, in particular, have emerged as indispensable members of the diabetes care team—interacting with patients far more frequently than most other providers and positioned to identify problems, reinforce education, and advocate for access.

Despite significant advances in insulin pharmacology and delivery, gaps in patient understanding, affordability challenges, and the growing use of combination therapies such as glucagon-like peptide-1 (GLP-1) receptor agonists have introduced new clinical considerations. Jennifer Griffin, PharmD, MS, a clinical pharmacist at Harps Food Stores, shares her insight on insulin management as a community pharmacist.

What is the fundamental difference between basal (long acting) and prandial (bolus) insulin?

Long-acting insulin like glargine, degludec, and detemir are used to cover a patient’s basal metabolic insulin requirement. They work to regulate the body’s insulin needs during fasting, or simply put, in-between meals and overnight by regulating hepatic glucose production. On the other hand, short-acting insulin like lispro and aspart are used to manage glycemic excursions after meals. As clinicians, we will adjust a patient’s basal insulin if we notice patterns in glycemic excursions during fasting periods, and we will adjust prandial insulin based on postprandial glucose excursions.

What is the standard protocol if a patient misses a dose of their basal insulin versus their mealtime bolus?

There are many factors that play into this, such as time since missed dose, current and anticipated blood glucose, proximity to next dose, type of insulin regimen, and other patient-specific factors. For basal insulin, if a patient just missed their dose, it may be reasonable to administer it right away, but if the patient is closer to their next dose, it would be safer to wait and administer it at the next scheduled time, assuming a 24-hour duration of action. If a patient misses their mealtime insulin by several hours, it may be recommended to skip the dose completely. If the patient has already eaten and remembers shortly after, the patient may be recommended to administer a decreased dose of bolus insulin. Regarding mealtime insulin dosing, the patient may have a good understanding of how to perform calculations to administer a particular dose to correct their blood glucose.

What strategies can community pharmacies use to help patients manage insulin affordability and access?

The main strategy we use to manage insulin affordability and access is communicating with insurance plans and prescribers. For example, an insurance company may only pay for a specific long-acting insulin as opposed to another. A pharmacist can communicate with the prescriber to select a product that is covered by a patient’s insurance plan. Another example that I have encountered recently is that an insurance plan requests a specific product, but it is unavailable for us to order and is unavailable at all other local pharmacies. In this situation, we can call the insurance and advocate that the patient needs this particular insulin, arguing that the product the insurance will pay for is currently unavailable. Usually, we can get the insulin covered for the patient.

What role does the pharmacist play in integrating CGM data with insulin therapy?

Pharmacists routinely play a role in assisting and educating patients on utilizing CGMs. We educate patients on device application, device usage, and how to understand the data. Diabetes management requires ongoing education, and having a pharmacist who sees a patient 12 or more times a year is going to lead to improved A_1C reduction—evidence shows CGM-integrated pharmacist services achieve A_1C reductions of 0.4% to 2.9%. If pharmacists were paid for consults with patients with diabetes, we could provide sufficient staffing to provide education to all diabetic patients. Currently, we provide these services in the most overt situations we encounter.

What are the clinical considerations when a patient is prescribed a combination of insulin and a GLP-1 receptor agonist?

Without appropriate insulin dose reductions, GLP-1 receptor agonists and insulin increase the patient’s risk of experiencing hypoglycemia as compared with GLP-1 monotherapy. As the patient begins treatment with a GLP-1, providers need to be prepared to adjust the patient’s insulin therapy as needed. We would expect to have to make adjustments in a patient’s insulin regimen when a GLP-1 is added and when the dose of the GLP-1 is increased. According to the American Diabetes Association, it is recommended to first decrease and discontinue bolus insulin and then begin to reduce the basal insulin dose as necessary based on the patient’s glucose patterns.¹

Conclusion

Effective insulin management extends well beyond selecting the right formulation. It requires individualized clinical decision-making, consistent patient education, and a coordinated care team working in concert. As the therapeutic landscape continues to evolve with the rise of CGM technology and the growing use of GLP-1 receptor agonists alongside insulin, pharmacists must remain vigilant about adjusting regimens proactively and communicating clearly with patients about what to expect.

Pharmacists occupy a uniquely valuable position in this ecosystem. With touchpoints that far exceed those of most other providers, they are well-placed to reinforce education, bridge access gaps, and flag safety concerns before they become clinical problems. Expanding reimbursement structures to reflect this role would allow pharmacy teams to deliver the level of diabetes support that the evidence already supports. Ultimately, optimizing insulin therapy is less about any single intervention and more about building the systems and relationships that allow patients to manage a complex, lifelong condition with confidence.