Minor
Established
Mô tả
Ranitidine competitively inhibits OCT2-mediated renal tubular secretion of metformin, modestly increasing metformin plasma concentrations.
Cơ chế
Both ranitidine and metformin are organic cations secreted by OCT2 and MATE transporters in the renal proximal tubule; competition for these transporters raises metformin AUC slightly.
Ý nghĩa lâm sàng
A pharmacokinetic study showed ranitidine increased metformin AUC by approximately 35%; this is unlikely to cause lactic acidosis in patients with normal renal function.
Xử trí
No routine dose adjustment required; caution in patients with renal impairment or other risk factors for lactic acidosis.