Insulin remains the lifesaving foundation of type 1 diabetes treatment, but a growing number of doctors are adding medications originally designed for type 2 diabetes to help their patients achieve better blood sugar control and reduce daily insulin doses. These off-label medications include GLP-1 receptor agonists (like Ozempic), metformin, and SGLT-2 inhibitors, which work through different mechanisms to improve how the body handles glucose. However, using these drugs in type 1 diabetes carries unique risks that require close medical supervision and a cautious approach to dosing.

Why Are Doctors Adding Type 2 Diabetes Drugs to Type 1 Treatment?

The shift reflects a practical reality: improved insulin therapies and glucose monitoring technology have allowed people with type 1 diabetes to live increasingly normal lifestyles, but this has also led to rising rates of obesity within the community. Additionally, some people with type 1 diabetes develop high insulin resistance, meaning their bodies require very large daily insulin doses to keep blood sugar in range. Doctors are exploring adjunct medications to address these challenges.

"More and more clinicians are using GLP-1s off-label in people with type 1 diabetes, particularly in those who also have obesity or high insulin requirements," said Mihail Zilbermint, MD, an associate professor of medicine at Johns Hopkins University School of Medicine and the chief of the division of endocrinology, diabetes, and metabolism at Suburban Hospital in Maryland.

Mihail Zilbermint, MD, Associate Professor of Medicine at Johns Hopkins University School of Medicine

The three main medication classes being used off-label each offer distinct benefits for people with type 1 diabetes.

What Are the Key Benefits of These Off-Label Medications?

Research and clinical experience have identified several ways these type 2 diabetes medications can improve outcomes for people with type 1 diabetes. The benefits vary depending on which medication is used, but they generally center on reducing insulin requirements, improving blood sugar control, and supporting weight loss.

• GLP-1 Receptor Agonists: These medications help the body become more sensitive to insulin, which can lead to significantly lower insulin doses. They also promote weight loss, making diabetes management easier for people carrying extra weight. However, they carry an increased risk of hypoglycemia (low blood sugar), which is why the FDA has been hesitant to approve them for type 1 diabetes.
• Metformin: This affordable, long-established medication can lower total daily insulin needs by an average of 0.61 units per kilogram in adolescents and 0.44 units per kilogram in adults. It may also reduce A1C (a measure of average blood sugar over three months) by about 0.3 percentage points and support modest weight loss.
• SGLT-2 Inhibitors: These drugs work by increasing the amount of sugar excreted in urine, which can improve A1C by 0.20 to 0.45 percentage points while also improving time in range (the percentage of time blood sugar stays within target). One study found that after one year, people with type 1 diabetes taking an SGLT-2 inhibitor had an average weight loss of 4.4 percent, with some trials in overweight individuals reporting up to 13.3 percent reduction in body weight.

What Risks Come With Off-Label Use in Type 1 Diabetes?

Despite their potential benefits, these medications carry serious risks when used in people with type 1 diabetes. The most concerning is hypoglycemia, or dangerously low blood sugar, which can occur because these drugs lower blood sugar through mechanisms that don't account for the fact that people with type 1 diabetes cannot produce their own insulin to prevent drops. This is the primary reason the FDA has not approved GLP-1s for type 1 diabetes use.

SGLT-2 inhibitors present an additional concern: they can increase the risk of urinary tract infections and vaginal infections because they increase sugar in the urine. More seriously, they carry a risk of diabetic ketoacidosis, a life-threatening condition where the body produces too many ketones and the blood becomes too acidic.

"The main goal in type 1 diabetes management is to try and minimize the amount of insulin that might be required," said Dace Trence, MD, the president of American Association of Clinical Endocrinology and a professor emeritus at the University of Washington in Seattle.

Dace Trence, MD, President of American Association of Clinical Endocrinology

How Should People With Type 1 Diabetes Approach Off-Label Medications?

Medical experts emphasize that off-label use of these medications requires careful planning, close monitoring, and a slow approach to dosing adjustments. Because of hypoglycemia risks, doctors may prescribe very small doses of GLP-1s, especially to people who don't have significant weight to lose. Metformin is often preferred as an initial add-on because it's relatively affordable, has been used for decades, and carries fewer acute risks than other options.

Trence stressed the importance of patience and communication: "People with type 1 diabetes also need to understand that this is a process. We need to go slow and make sure that you don't have any problems such as low blood sugar." She also noted that metformin can serve as an easy add-on treatment for many patients.

Trence

Anyone considering off-label medication use should have a detailed conversation with their endocrinologist about both the potential benefits and the specific risks they might face based on their individual health profile. This discussion should include how the medication will be dosed, how often blood sugar will be monitored, and what warning signs to watch for.

Steps to Take Before Starting Off-Label Medications for Type 1 Diabetes

• Schedule a Consultation: Meet with your endocrinologist to discuss whether off-label medications might be appropriate for your specific situation, including your current insulin requirements, weight, and overall health status.
• Understand the Risks and Benefits: Ask your doctor to explain how the medication works, what benefits you might expect based on research, and what specific risks apply to you personally.
• Plan for Monitoring: Establish a clear monitoring schedule with your healthcare team, including how often you'll check blood sugar, when you'll have follow-up appointments, and how your insulin doses will be adjusted as the medication takes effect.
• Learn Warning Signs: Ask your doctor about symptoms of hypoglycemia and diabetic ketoacidosis (if taking SGLT-2 inhibitors), and know when to seek emergency care.

The use of type 2 diabetes medications in type 1 diabetes represents an evolving area of clinical practice. While these drugs offer genuine potential to reduce insulin burden and improve metabolic health for some people, they are not appropriate for everyone and require individualized decision-making under expert supervision.