Fe: May reduce absorption of cefdinir, bisphosphonates, carbidopa/levodopa, entacapone, fluoroquinolone, levodopa, levothyroxine, methyldopa, mycophenolate mofetil, penicillamine, & tetracyclines. Vit B
1: High doses may enhance neuromuscular blocking agent eg, tubocurarine Cl, metocurine iodide, pancuronium Br & vecuronium Br. Vit B-complex: Blood levels may be reduced w/ phenobarb or phenytoin. May result in enhanced anticoagulant response of anticoagulant eg, warfarin, aspirin. Folic acid: Folic acid consumption can be depleted w/ MTX, NSAIDs eg, ibuprofen, naproxen, or diclofenac.