Organic cation transporter 2 (SLC22A2)
Also known as: OCT2, SLC22A2, ROCT
Uptake transporter (SLC22A2) expressed in the proximal renal tubules and kidney, responsible for tubular secretion of cationic drugs such as metformine, ranitidine and dolutegravir. Also relevant in the elimination of cisplatin and procainamide.
OCT2 inhibition (e.g. cimetidine, trimethoprim) reduces tubular secretion of metformine, raising plasma concentrations and the risk of adverse effects (lactic acidosis). Ranitidine is both a substrate and a weak OCT2 inhibitor.
Substrates: metformine, ranitidine, dolutegravir, procainamide, cisplatin, dofetilide.
Inhibitors: cimetidine, trimethoprim, dolutegravir, ranitidine (weak), procainamide (competition).
Inducers: there are no clinically relevant inducers documented.
The metformine + cimetidine/trimethoprim interaction may raise the risk of lactic acidosis; monitor renal function when combined with OCT2 inhibitors.
DailyMed/FDA (NIH/NLM) — approved labels (metformine, ranitidine, dolutegravir); EMC-UK (MHRA) — SmPC
