May increase AUC & C
max of digoxin. Closely monitor to maintain adequate glycemic control of patients concomitantly taking drugs that produce hyperglycemia eg, Ca channel blockers, corticosteroids, diuretics [eg, thiazides], estrogen, hormonal contraceptives, INH, nicotinic acid, phenothiazines, phenytoin, sympathomimetics, thyroid products. May decrease AUC and C
max of glyburide. Increased risk of hypoglycemia w/ meglitinides [eg, nateglinide, repaglinide], & sulfonylureas. Metformin: Potentiated hypoglycemic effects & effects on lactic acidosis w/ alcohol. May compete for renal tubular transport w/ cationic drugs eg, amiloride, digoxin, morphine, procainamide, quinidine, ranitidine, triamterene, trimethoprim & vancomycin. Increased plasma levels w/ cimetidine. Decreased extent of & slightly delayed absorption w/ food. Increased AUC & C
max w/ furosemide, decreased AUC & C
max of furosemide. Increased AUC & C
max w/ nifedipine. Decreased GFR & increased risk of lactic acidosis w/ NSAIDs eg, indomethacin & rofecoxib. Increased risk of lactic acidosis w/ parenteral iodinated contrast media. Sitagliptin: Increased AUC & C
max w/ cyclosporine.