It is considered the first choice for monotherapy in diabetes treatment.9,10 Metformin functions by activating the AMPK (Adenosine Monophosphate-activated Protein Kinase) enzyme, which plays a role in regulating genes related to hepatic gluconeogenesis, thereby decreasing hepatic glucose production, reducing intestinal absorption, and enhancing insulin sensitivity.11 In general, metformin is considered safe and well tolerated. This evidence concerns the gene INS and diabetes mellitus.