Type 1 diabetes: Medications that can help beyond insulin

When we talk about type 1 diabetes (T1D), insulin is at the centre of the conversation because it is essential for survival. But did you know that other medications can sometimes be used alongside insulin to support diabetes management?

A complement to insulin

Some people living with T1D may face specific challenges, such as significant blood glucose fluctuations, weight gain, insulin resistance or difficulty reaching their blood glucose targets.

In some situations, medications called adjunctive therapies may be considered in addition to the main treatment. Their purpose is not to replace insulin, but rather to help improve blood glucose management or address specific needs. These medications are generally used to treat type 2 diabetes, but they may also have beneficial effects for people living with T1D.

Examples of adjunctive medications include metformin (Glucophage), GLP-1 receptor agonists (e.g., tirzepatide (Mounjaro), semaglutide (Ozempic)), and SGLT-2 inhibitors (e.g., empagliflozin (Jardiance), canagliflozin (Invokana)).

These medications may, among other things:

• reduce certain blood glucose fluctuations
• reduce insulin requirements in some cases
• support weight management
• help prevent long-term diabetes complications

However, these medications are not appropriate for everyone and require an assessment of their potential benefits and risks by a healthcare professional. They are prescribed off-label, as they are not approved by Health Canada for the treatment of T1D.

Explore the full course

Which medications can be used as adjunctive therapies in T1D? How do they work, and what are their benefits and potential side effects?

Log in to access the full course and learn about the different classes of adjunctive medications, the latest scientific evidence, and situations in which adding an adjunctive medication may be considered.

References

• Diabetes Canada Clinical Practice Guidelines, Glycemic Management Across the Lifespan for People with Type 1 Diabetes
• Masouri MM, Ebrahimi R, Noori S. An Updated Systematic Review and Meta-Analysis on the Efficacy and Safety of Metformin as Add-on Therapy to Insulin in Patients With Type 1 Diabetes. Endocrinology, Diabetes & Metabolism. 2025 Jul;8(4):e70060. doi: 10.1002/edm2.70060. PMID: 40512873; PMCID: PMC12165280.

Written by:
Amélie Roy-Fleming, RD, MSc, CDE

Reviewed by:
Sarah Haag, RN, B.SC.