Minor
Suspected
説明
Amoxicillin may slightly potentiate warfarin by reducing gut flora that synthesize vitamin K2, though the effect is generally small and inconsistent.
機序
Broad-spectrum antibiotic activity against intestinal bacteria that produce menaquinones (vitamin K2), potentially reducing cofactor availability for hepatic coagulation factor synthesis.
臨床的意義
The interaction is usually modest; however, patients with marginal dietary vitamin K intake may show clinically significant INR increases.
対処法
Consider INR check midway through and after completing a course of amoxicillin, especially in patients with variable diets.