Treatment of Uncontrolled Glucose Levels Without GLP-1 Receptor Agonists

First-Line Treatment Options

The American Diabetes Association recommends metformin as the cornerstone of therapy for patients with type 2 diabetes, to be initiated if eGFR ≥30 ml/min per 1.73 m² and continued as long as it's tolerated and not contraindicated 1, 2
SGLT2 inhibitors with proven cardiovascular and kidney benefits should be added to metformin for patients with eGFR ≥20 ml/min per 1.73 m² 3
For patients with eGFR <30 ml/min per 1.73 m², metformin should be discontinued, and SGLT2i can be used as long as eGFR remains ≥20 ml/min per 1.73 m² 1, 2

DPP-4 inhibitors can be considered for patients who need additional glycemic control beyond metformin and SGLT2i, with a neutral effect on weight and low risk of hypoglycemia when used without insulin or sulfonylureas 2
Thiazolidinediones (TZDs) can be effective, particularly in patients with insulin resistance, but should be used with caution in patients with or at risk for heart failure due to potential fluid retention 2
Sulfonylureas can be used when cost is a major concern, but require close monitoring for hypoglycemia, especially in elderly patients or those with irregular eating patterns 2
Insulin therapy may be necessary for patients with significantly elevated glucose levels or symptomatic hyperglycemia, and can start with basal insulin and add prandial insulin if glycemic targets are not met 4

For patients with established cardiovascular disease, prioritize SGLT2i with proven cardiovascular benefits 3
For patients with heart failure, SGLT2i are strongly preferred due to their proven benefits in reducing heart failure hospitalizations, while avoiding TZDs due to risk of fluid retention 2
For patients with chronic kidney disease (CKD), use SGLT2i for eGFR ≥20 ml/min per 1.73 m², and consider DPP-4 inhibitors or insulin for eGFR <20 ml/min per 1.73 m² 1, 2
For patients concerned about weight gain, SGLT2i are preferred as they promote weight loss, while DPP-4 inhibitors are weight-neutral alternatives 2, 5

For metformin, start with low dose (500-850 mg daily) and titrate gradually, reducing dose when eGFR is 30-44 ml/min per 1.73 m² 1

Discontinue metformin when eGFR falls below 30 ml/min per 1.73 m² due to increased risk of lactic acidosis 1, 2
Monitor renal function regularly in patients on SGLT2i, particularly those with tenuous renal function 3
Be aware that DPP-4 inhibitors should not be used in combination with GLP-1 RAs (if the patient later reconsiders GLP-1 RA therapy) 1
Insulin therapy requires careful education on administration and hypoglycemia management 4
When combining multiple agents, consider potential drug interactions and additive side effects 3