If starting a GLP-1, which class of medication should be discontinued due to no additional benefit?

When considering the concurrent use of medications for the treatment of obesity and related conditions, it's important to understand the mechanisms and benefits of each class. GLP-1 receptor agonists, which are used to promote weight loss and improve glycemic control, work by enhancing insulin secretion, suppressing glucagon secretion, and slowing gastric emptying.

DPP-4 inhibitors, on the other hand, also aim to improve glycemic control by inhibiting the enzyme dipeptidyl peptidase-4, which breaks down incretin hormones like GLP-1. When a patient starts therapy with a GLP-1 receptor agonist, the DPP-4 inhibition may not provide additional benefits in terms of glycemic control due to the enhanced effects already being exerted by the GLP-1 agonist. Essentially, the actions of the GLP-1 receptor agonist make the presence of a DPP-4 inhibitor redundant, as both drugs target similar pathways in regulating glucose metabolism.

In contrast, SGLT2 inhibitors and insulin sensitizers, including thiazolidinediones, work via different mechanisms—SGLT2 inhibitors promote glucose excretion in urine and potentially help with weight loss, while insulin sensitizers improve insulin action