People with type 1 diabetes (T1D) take insulin to help keep blood glucose (BG) levels within their recommended target range. But insulin isn’t the only drug that can influence BG levels. In fact, at least six other types of medications can do this. 

These medications are most commonly used to lower BG levels in people with type 2 diabetes, but researchers have been working to find out if they can help people living with T1D, too. While these medications help to lower BG, they work differently than insulin.  

Research suggests taking them in addition to insulin could help make BG management easier and more effective. When drugs are used in this way — to assist a primary medication — they are known as “adjunct therapies.” 

  

Potential adjunct therapies for T1D 

Different adjunct therapies work in different ways. For example, one type works by mimicking the action of hormones called glucagon-like peptide-1 (GLP-1) and gastric-inhibitory peptide (GIP). These hormones occur naturally in your body, where they help to maintain BG levels, but they break down quickly. Medications that mimic them last longer than the hormones themselves do, so they can keep working to modulate glucose levels.  

There are many GLP-1 mimics, or drugs that work by imitating this hormone, including: 

  • Semaglutide (Ozempic, Wegovy, and Rybelsus)
  • Liraglutide (Victoza and Saxenda) 
  • Tirzepatide (Mounjaro), which mimics both GLP-1 and GIP 

Another type of adjunct therapy works by blocking a protein called sodium-glucose cotransporter-2 or SGLT2. SGLT2 moves glucose from your kidneys back into your bloodstream. Blocking SGLT2 causes glucose to leave the body by urination instead. Commercially available drugs of this type include: 

  • Empagliflozin (Jardiance) 
  • Dapagliflozin (Farxiga) 
  • Sotagliflozin (Zynquista and Inpefa) 

  

What are their benefits and risks? 

One major benefit of adjunct therapies is that they can help to improve BG management. This can result in several things:  

  • Lower hemoglobin A1C levels, which reflect average BG levels 
  • Decreased insulin needs 
  • More time spent in your glucose target range 

In addition, adjunct therapies like GLP-1 mimics and SGLT2 blockers may help with weight management and prevent heart damage. SGLT2 blockers can also help to protect your kidneys. 

However, these medications have some drawbacks as well. For GLP-1 mimics, one of the biggest risks is hypoglycemia (low BG). They can also have gastrointestinal side effects such as nausea, vomiting, diarrhea, and constipation. For SGLT2 blockers, their use has potential links with diabetic ketoacidosis (DKA) and dehydration. 

More evidence is needed to determine whether the benefits of using adjunct therapies for T1D outweigh the risks. 

  

What does the latest research suggest?  

Scientists continue to study the use of adjunct therapies in T1D. New results were presented at the American Diabetes Scientific Sessions last month.   

Two different studies suggested that the GLP-1/GIP mimic tirzepatide could reduce hemoglobin A1C levels, body weight, and insulin requirements without causing hypoglycemia. In addition, data from the T1D Exchange Quality Improvement Collaborative (T1DX-QI) showed that GLP-1 mimics lowered hemoglobin A1C levels among people living with T1D.   

Results of a study of the SGLT2 blocker dapagliflozin suggested that the drug was safe and effective in teens with T1D. The trial included a strategy designed to reduce the risk of DKA, and only one case of DKA occurred among almost 100 participants. It was a mild case and developed in a person who received dapagliflozin. 

Researchers are also looking at the potential effects of medications like semaglutide on eye health in people with type 2 diabetes. The 5-year study is called FOCUS, and results are expected by the end of 2027.   

  

What does this mean for people living with T1D?  

Insulin therapy is essential for people with T1D – but it is not perfect. BG management is challenging under the best circumstances. Insulin therapy can lead to an increased risk of weight gain. And living with T1D can increase the risk of developing heart and kidney disease. Adjunct therapies that can safely address these findings could decrease some burdens associated with T1D.  

In a survey, 75% of T1DX-QI adult endocrinology clinics said that GLP-1 mimics have a role in T1D management as an adjunct therapy. With more clinical trials, we will better understand the benefits and risks of these therapies for people living with T1D.  

Various studies of adjunct therapies in T1D are in progress (a table in this detailed article on adjunct therapies lists some of them).  

You can participate in type 1 diabetes research from home — by joining the T1D Exchange Registry! It’s free, it only takes 15 minutes to get started, and you’ll have access to ongoing studies and surveys that help improve life for people with T1D.