Going into 2026, widespread shortages of most major diabetes medications had largely stabilized: The shortages of Humulin and lispro insulin vials, and therefore medications, that dogged Indianapolis-based Eli Lilly in spring and summer 2024 have resolved, and it, like other manufacturers, has largely caught up with much of the demand for its GLP-1 products as well. 

However, experts from the advocacy group T1D Strong say that shortages of GLP-1 receptor agonists, basal and rapid-acting insulin analogues, and several frontline oral agents are expected to persist into 2026 as the supply chain remains unstable, and especially in certain geographic pockets. 

When shortages occur, it often falls to primary care clinicians to improvise substitutions and bridge strategies, while hospitalists see the downstream effects of shortages in real time in patients who show up with conditions like dehydration, medication errors, and avoidable admissions. The challenge has shifted from simply locating medication to building structured, risk-based strategies that prevent treatment gaps and protect the most vulnerable patients. 

Safe Substitutions: What Works, and What Creates Risk 

Clinicians emphasize that the most stable substitution is no substitution at all. 

"That may mean dispensing a different approved strength of the same product or spacing out doses to bridge a short-term shortage," said Fady Hannah-Shmouni, MD, an endocrinologist and medical director with Eli Health. "When needed, you can substitute to another GLP-1 receptor agonist at an equivalent, clinically established dose, with appropriate titration; GLP-1-to-GLP-1 switches tend to be less destabilizing if dose mapping is done carefully."

Hannah-Shmouni said there are a wide range of reasonable alternatives if this kind of switch is not possible, but alternative agents require closer monitoring due to differences in mechanism, side-effect profile, and titration needs. These options include SGLT2 inhibitors, prandial insulin, metformin, DPP-4 inhibitors (which are often combined with another agent for fasting glucose), TZDs, sulfonylureas, and basal insulin.

Unplanned or poorly structured switches remain a major source of clinical deterioration.

"You want to avoid ad hoc GLP-1 switches without dose matching or titration planning — those are a setup for glycemic instability and adverse effects," Hannah-Shmouni said. "Even more concerning are fraudulent or unregulated 'GLP-1' products and supplements claiming GLP-1-like effects." During the shortages, there has been a surge of these unregulated products, he said, and "they pose serious safety, efficacy, and quality-control risks."

When Shortages Hit: Guidelines for Decision-making

When it comes to life-sustaining drugs like those for diabetes, decision-making in the face of shortages can be fraught. Eve K. Pennie, MD, a physician and epidemiologist with the Texas Department of State Health Services, said substitutions should be guided by structured prioritization rather than reactive decision-making.

"Primary care clinicians need a framework for decisions when medication availability is limited," she said.

This framework should prioritize continuity, safety, and individual risk rather than first-come, first-served approaches, Pennie said. 

"I suggest that clinicians ask themselves three questions before reallocation: Who is most likely to decompensate without this medication? Who has reasonable alternatives? And who is using this medication primarily for glycemic control rather than weight reduction or improvement of other cardiometabolic factors?"

For example, she said, a patient with type 2 diabetes and an elevated A1c with a history of hypoglycemia on insulin would be expected to derive greater benefit from a GLP-1 than a lower-risk patient taking GLP-1 for weight loss, Pennie said.

She said that basal insulin shortages require similarly careful triage and recommended prioritizing the maintenance of basal coverage at a clinically appropriate dose. Pennie said that for these patients, she would recommend transitioning to another basal analog using accepted dosing conversions if necessary, and monitoring the patient closely, rather than leaving the patient without basal coverage.

Pennie also recommends creating individualized "shortage plans" for diabetic patients before problems arise.

"Written 'shortage plans' in the patient's medical record detailing alternative medications, doses, and strategies for managing shortages will assist the clinician in avoiding treatment gaps when the pharmacy rejects a patient's prescription due to a shortage."

Who Cannot Afford a Gap 

Drug interruptions do not affect all patients equally. Some deteriorate rapidly with even brief lapses in therapy.

"The guiding principle is to protect patients at highest clinical risk from interruption," said Hannah-Shmouni.

That includes people with type 1 diabetes, prior DKA or severe hyperglycemia, hypoglycemia unawareness, advanced complications, pregnancy, and those who have just achieved or are still in the middle of titration to good control, he said. 

"For those patients, maintaining the same product and dose, or substituting an approved equivalent strength of the same drug, is the least destabilizing option," he said. 

Because GLP-1 RAs differ in dosing interval and pharmacokinetics, and basal insulins differ in duration and variability, clinicians use structured triage frameworks: clinical acuity, therapeutic stability, and substitution feasibility.

Hannah-Shmouni said for volatile or fragile patients, having a backup plan even when their originally prescribed medication is in place is particularly important. He said that should include not just each patient's "plan B" with respect to medication, but all the details surrounding what to do in case of a shortage, including GLP-1 dose-equivalency charts, dose spacing options, temporary strength substitutions, and information on pharmacies to use as partners for partial fills. He said this helps prevent clinicians from having to make not only decisions, but also calculations, under pressure.

Shortages can also disproportionately impact those in marginalized communities. Monica Harmon, MPH, RN, who was the executive director of a community wellness center in West Philadelphia for many years and is now a private community health consultant, said she has seen patients who have difficulty adhering to diabetes treatment because of their history, comorbid conditions, social or financial situations, pharmacy access, or other situations succeed when prioritized for care team intervention. 

"This includes weekly team meetings, flagging for RN education and follow-up, social work involvement, behavioral health, nutrition, communications with the system pharmacy, and local pharmacies," said Harmon, who led the team at the Community Wellness HUB, affiliated with Drexel University.

Harmon said community practitioners should offer a wide range of counseling strategies to prevent timing errors and glycemic volatility after a switch is necessitated. 

"We make assessments of patients' preferred learning styles, provide RN education, nutrition, coordination with behavioral health and social work, utilization of community resources for more education, food selection, and use of language phone lines if a health care provider does not speak the preferred language that the client best understands," Harmon said. "I've also seen coordination for those who are living with low vision or no vision, and the introduction of other complementary therapies, such as yoga, fitness, Reiki, etc."

Harmon said that her staff was alerted to medication shortages by practice managers, so that they could stay abreast of changing dynamics in the patient population's needs. 

When Shortages Show Up in the Hospital 

Hannah-Shmouni and Pennie both said that when a medication shortage results in a diabetic patient requiring inpatient admittance, the first job is getting them stabilized metabolically. Then, it becomes a detective job, determining what medication has been interrupted, for how long, and what the patient's response was — did they skip a dose or doses, ration their insulin, try an alternative, or use a nonprescribed product?

The doctors ticked off a number of potential issues to look out for while in the midst of these treatments. 

"The common pitfalls are very consistent: restarting a GLP-1 at the full prior dose after a long interruption, relying on sliding-scale insulin alone, treating GLP-1s or basal insulins as interchangeable without dose mapping, underestimating dehydration and ketosis, and failing to design a post-discharge plan that acknowledges ongoing shortages," said Hannah-Shmouni.

Pennie echoed those points, adding that continuing a complex home regimen that cannot be safely replicated in the inpatient environment is often an issue. She also said that involving pharmacy and/or endocrinology early when a patient is on multiple high-risk agents is imperative.

"Another important consideration is not planning discharge until the health care team is aware of which agents are available in the patient's community, which results in unnecessary hospital readmissions when the 'ideal' regimen is not accessible," Pennie said.

Preventing Complications Through Patient Education 

Diabetes nurse educator Carole Jakucs, MSN, RN, PHN, based in Los Angeles, notes that many destabilizations stem not from the substitution itself but from technique or timing errors.

"It's critically important to ensure patients understand exactly how to administer their new injectables or how to take their new oral medications. If a patient is using insulin for the first time, teaching them about injection technique, site rotation, and proper storage are all important."

Jakucs said timing of doses is a recurring problem area, and that many times, patients don't have this information. She said that correct timing of doses stabilizes patients' metabolism and that adherence is boosted by clear, redundant instructions, and by an understanding of their own physiology.

"Patients should be instructed at the point of care, verbally and in writing, so they remember all of this information once they are home. They really need to know how the different insulins work … as it helps with their compliance and taking them correctly at the appropriate times."

No reported disclosures.