Linagliptin: Increased AUC & Cmax
w/ ritonavir. Decreased steady-state AUC & Cmax
w/ rifampicin. Increased plasma AUC & Cmax
of simvastatin. Metformin: Intrinsic hyperglycaemic activity w/ glucocorticoids, β2
-agonist & diuretics. Increased risk of lactic acidosis w/ alcohol intoxication, NSAIDs eg, COX2 inhibitors; ACE inhibitors, AIIA, diuretics. Reduced efficacy w/ OCT1 inhibitors eg, verapamil. Increased GI absorption & efficacy w/ OCT1 inducers eg, rifampicin. Increased plasma conc w/ OCT2 inhibitors eg, cimetidine, dolutegravir, ranozaline, trimethoprim, vandetanib, isavuconazole. Altered efficacy & renal elimination w/ OCT1 & OCT2 inhibitors eg, crizotinib, olaparib. Not recommended in combination w/ iodinated contrast agents.