New guidance on the use of GLP-1-based drugs in people with type 1 diabetes (T1D), due to be published later this year, will address the safety and optimal use of these medications which are currently used off-label in this patient population.

Although the use is off-label, it has been increasing in recent years, particularly as an adjunct to insulin in people with T1D who also have obesity and/or cardiovascular disease, said Satish K. Garg, MD, professor of medicine and pediatrics at the Barbara Davis Center for Diabetes, University of Colorado, Denver, who presented an overview of the upcoming guidelines at 19th International Conference on Advanced Technologies and Treatments for Diabetes (ATTD) 2026.

“In the old days, we used to be told people with type 1 diabetes are lean and thin and will never get overweight and obese. That was, in fact, one of the ways to distinguish people with type 1 and type 2 diabetes. Unfortunately, that is no longer the case,” Garg said.

The upcoming Adjunctive Treatment with GLP/GIPs for Patients with T1D: A Consensus Report and Guidelines for Safe Use, will be published in the June 2026 issue of the ATTD journal Diabetes Technology and Therapeutics, for which Garg is editor-in-chief.

“I really want you to pay attention to the two words we have used in the title itself, ‘adjunctive and a safe use,’ because we are talking about people with type 1 diabetes,” he said. 

Go Slow, Adjust Insulin

The consensus recommendations, some of which were published in a 2024 editorial in the same journal, are expected to include the following, said Garg.

• Start slow and adjust the GLP-1/glucose-dependent insulinotropic polypeptide (GIP) doses gradually. The full dose for T1D may not need to be as high as that typically used for T2D and obesity.

“The usual full dose that is recommended for people with type 2 diabetes, which in the case of tirzepatide goes all the way up to 15 mg weekly, is usually not the most acceptable or tolerable dose [in T1D],” he explained.

“The majority of our patients are able to achieve the target weight and the benefits by 7.5 to 10 mg,” he added.

• Insulin dose should be titrated carefully to avoid hyperglycemia, ketosis, diabetic ketoacidosis, and hypoglycemia. The typical recommendation is to cut the insulin dose by 20%, but that may vary among individuals.

“The most important part, whenever you start a GLP analog in people, whether semaglutide or tirzepatide or oral Wegovy,” said Garg, is to “please be careful about insulin dose.”

“You need to individualize treatment in people…most of the dose reduction happens in the prandial, not the basal insulin dose,” he cautioned.

Asked to comment, Francine R. Kaufman, MD, Distinguished Professor Emerita of Pediatrics and Communications, Keck School of Medicine of University of Southern California, Los Angeles, told Medscape Medical News, “This is where [continuous glucose monitoring] is really imperative, and where remote monitoring is important. You’re not going to see these patients all the time, but somebody needs to educate them and be sure that the therapy is having a positive effect and no negatives.”

Baseline Labs, Monitor and Treat Side Effects

Garg also presented the following recommendations:

• Baseline labs should include thyroid-stimulating hormone, uric acid, albumin excretion rate, albumin/creatinine ratio, eGFR, etc. Doses of thyroxine, statins, and blood pressure medications may also require adjustment on follow-up.
• Mitigate gastrointestinal side effects, including nausea/vomiting and constipation/overflow diarrhea.

For this, “there are a lot of new drugs that might help,” he noted.

• Baseline eye exam should be conducted and repeated sooner than 1 year if needed.

This is due to some data suggesting worsening diabetic retinopathy in people with T1D after initiating GLP-1 or GLP/GIP agents, mostly associated with rapid improvement in glycemic control, a long-recognized phenomenon. “If their eyes are compromised, you might want to keep a close watch on it,” Garg said.

In addition:

• Sarcopenia should be assessed and nutritional management is recommended, although sarcopenia wasn’t seen frequently in the randomized controlled trials.

“You may want to pay attention to the nutritional intake, but don’t be aggressive,” he advised.

• Provide prescriptions for glucagon and ketone strips, with an eye toward continuous ketone monitoring if approved in the future.
• Consider reducing the dose of the GLP-1 receptor agonists or GLP/GIP once the desired weight is reached, and providing a maintenance dose.

Garg said, “it’s up for discussion whether you should start reducing the dose of the GLP and how much you should reduce. We don’t have an answer because we are all still learning in this area…What is a maintenance dose of GLP-1/GIP in people with type 1 diabetes?”

Insurance Coverage for Patients With T1D

Garg raised another important issue for clinicians to consider:

• Consider cost and socioeconomic barriers.

In their 2024 paper, Garg and his colleagues included a discussion about insurance issues as claims for off-label use in T1D are often denied. Reimbursement for use in T1D may require prior authorization, with documentation that the individual with T1D also has insulin resistance, high insulin needs, and hypertriglyceridemia similar to T2D, which is sometimes called “double diabetes.”

In many cases, “the insurance company must see that the patient has tried and failed other medications, which delays the approval of the prescribed GLP analog,” they noted.

Kaufman said she has started doing that for some of her older adolescent patients with T1D who have obesity. “I will say they have elements of type 2…By the time they have obesity, they are usually on a higher insulin dose, so you can justify that they have insulin resistance.”

She’s had less success in obtaining coverage for patients with T1D based on obesity criteria alone, noting that “it comes back that they’re type 1 and excluded.”

Garg reported being on advisory boards and/or receiving consulting fees from Medtronic, Novo Nordisk, Dexcom, Roche Diagnostics, Abbott Diabetes Care, Vertex, and Eli Lilly. His institution received research grants from Eli Lilly, Novo Nordisk, Medtronic, Diasom, and Dexcom. He does not own stock in any device or pharmaceutical company. Kaufman reported being the chief medical officer of Senseonics, Inc.

Miriam E. Tucker is a freelance journalist based in the Washington, DC, area. She is a regular contributor to Medscape, with other work appearing in the Washington Post, NPR’s Shots blog, and Diatribe. She is on X @MiriamETucker and BlueSky @miriametucker.bsky.social.