Janovi, also known as selegiline phosphate, serving selegiline phosphate to lower blood sugar can be taken at the same time metformin, if the patient alone selegiline phosphate is not good at lowering blood sugar, can be taken together with metformin to lower blood sugar. Sitagliptin is a dipeptidyl peptidase 4 (DPP-4) inhibitor, which prevents dipeptidyl peptidase 4 from hydrolyzing enteric insulin, and can increase the level of active enteric insulin, which in turn acts to lower blood glucose levels. Metformin works by increasing insulin sensitivity in peripheral tissues, increasing glucose utilization in non-insulin-dependent tissues, inhibiting hepatic gluconeogenesis, and inhibiting glucose uptake by cells in the intestinal wall to lower blood glucose levels. Sitagliptin and metformin do not produce antagonism, so they can be taken together, but patients should not add or subtract drugs or adjust the dosage of drugs on their own, they should be adjusted under the guidance of physicians.