Is Insulin Still the Best Add-On? GLP-1 Drugs, DPP-4 Inhibitors, and SGLT2 Inhibitors Compared
Comparison of insulin versus established GLP-1 drugs, DPP-4 inhibitors, and SGLT2 inhibitors shows newer drug classes offer comparable glucose control with additional weight and cardiovascular benefits.
Quick Facts
What This Study Found
GLP-1 drugs, DPP-4 inhibitors, and SGLT2 inhibitors provide comparable glucose control to insulin with additional weight, cardiovascular, and kidney benefits.
Key Numbers
Multiple databases searched including Cochrane and PubMed. Compared three drug classes against insulin.
How They Did This
Comparative analysis of insulin versus GLP-1 RA, DPP-4 inhibitors, and SGLT2 inhibitors as add-on therapy in T2D.
Why This Research Matters
Insulin was the default add-on for decades. Establishing that newer peptide-based and non-insulin drugs are often superior helps shift prescribing away from insulin-centric approaches.
The Bigger Picture
The diabetes treatment hierarchy has been inverted. Instead of starting with simple drugs and escalating to insulin, modern guidelines now place GLP-1 drugs and SGLT2 inhibitors before insulin for most patients — a fundamental shift driven by their multi-organ benefits.
What This Study Doesn't Tell Us
Some patients still require insulin. T1D and very advanced T2D need insulin regardless. Cost and access to newer drugs vary by healthcare system.
Questions This Raises
- ?When is insulin still the best choice over GLP-1/SGLT2 drugs?
- ?Can GLP-1 drugs delay or prevent the need for insulin indefinitely?
- ?How do combination GLP-1+SGLT2 regimens compare to insulin-based regimens?
Trust & Context
- Key Stat:
- Beyond insulin GLP-1 drugs match insulin's glucose control while adding weight loss, heart protection, and kidney benefits that insulin cannot provide
- Evidence Grade:
- Strong evidence: comparative analysis based on extensive clinical trial data for multiple drug classes.
- Study Age:
- Published in 2025. Reflects the modern treatment hierarchy favoring GLP-1/SGLT2 over insulin.
- Original Title:
- Insulin Versus Established GLP-1 Receptor Agonists, DPP-4 Inhibitors, and SGLT-2 Inhibitors for Uncontrolled Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.
- Published In:
- Cureus, 17(9), e92175 (2025)
- Authors:
- Ahmed, Ammar, Tan, Zi, Abd El-Radi, Waddah, Rajamani, Krishnakumar
- Database ID:
- RPEP-09799
Evidence Hierarchy
Combines results from multiple studies to find an overall pattern.
What do these levels mean? →Frequently Asked Questions
Should I try GLP-1 drugs before insulin?
For most T2D patients, yes. GLP-1 drugs provide comparable blood sugar control to insulin while also promoting weight loss, protecting the heart, and preserving kidney function. Insulin may still be needed in advanced disease or T1D.
When is insulin still necessary?
Insulin remains essential for type 1 diabetes, very advanced T2D with minimal beta-cell function, diabetic ketoacidosis, and pregnancy. For most T2D patients, modern non-insulin options should be tried first.
Read More on RethinkPeptides
Cite This Study
https://rethinkpeptides.com/research/RPEP-09799APA
Ahmed, Ammar; Tan, Zi; Abd El-Radi, Waddah; Rajamani, Krishnakumar. (2025). Insulin Versus Established GLP-1 Receptor Agonists, DPP-4 Inhibitors, and SGLT-2 Inhibitors for Uncontrolled Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.. Cureus, 17(9), e92175. https://doi.org/10.7759/cureus.92175
MLA
Ahmed, Ammar, et al. "Insulin Versus Established GLP-1 Receptor Agonists, DPP-4 Inhibitors, and SGLT-2 Inhibitors for Uncontrolled Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.." Cureus, 2025. https://doi.org/10.7759/cureus.92175
RethinkPeptides
RethinkPeptides Research Database. "Insulin Versus Established GLP-1 Receptor Agonists, DPP-4 In..." RPEP-09799. Retrieved from https://rethinkpeptides.com/research/ahmed-2025-insulin-versus-established-glp1
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkPeptides research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.