Packer recently proposed an intriguing hypothesis that DPP-4 inhibitors potentiate some endogenous peptides, such as stromal cell-derived factor-1, in addition to activation of GLP-1, and that unfavorable effects of those peptides on CV parameters (e.g., inflammation, fibrosis, plaque growth, and sympathetic activation) could prevail against the CV protective effects of GLP-1, possibly leading to worsened CV complications and HF [36, 37]
Further information on lipohypertrophy and site rotation is available from Diabetes UK and the Forum for Injection Technique UK (FIT UK)
Keep vials upright, protected from light (wrap in aluminum foil or use amber vials if available), and away from the freezer compartment
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