Gatifloxacin Ferrous sulfate

Shiba K, Kus ima H, Momo K. The effects of aluminium hydroxide, dmetidine, ferrous sulfate, green tea and milk on pharmacokinetics of gatifloxacin in healthy humans. 

Ferrous fumarate, gluconate, sulfate and other iron compounds can reduce the absorption of ciprofloxacin, gatifloxacin, levofloxacin, moxifloxacin, norfloxacin, ofloxacin and sparfloxacin from the gut. Serum levels of the antibacterial may become sub-therapeutic as a result. Limited evidence suggests that fleroxacin is not affected and lomefloxacin is only minimally affected. Glemi-floxacin does not appear to interact when given 2 hours before or 3 hours after ferrous sulfate. No interaction appears to occur with iron-ovotransferrin. Zinc appears to interact like iron. 

A study in 6 healthy subjects found that ferrous sulfate 160 mg given with gatifloxacin 200 mg decreased fhe maximum serum levels and AUC of gatifloxacin by 49% and 29%, respectively. ... 

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