Lomefloxacin Antacids

Absorption Only 35-70% of oral norfloxacin is absorbed. However, 70-90% of the other fluoroquinolones are absorbed after oral administration. Bioavailability is greatest for ofloxacin and lomefloxacin. Intravenous preparations of ciprofloxacin and ofloxacin are available. Ingestion of the fluoroquinolones with sucralfate, antacids containing aluminum or magnesium, or dietary supplements containing iron or zinc can interfere with the absorption of these antibacterial agents. 

Information about the interactions with calcium carbonate is more limited than with the aluminium/magnesium antacids, but Table 10.3 , (p.329) shows that the bioavailabilities of ciprofloxacin and norfloxacin, and to a lesser extent gemifloxacin, can be reduced. These reductions are less than those seen with the aluminium/magnesium antacids, but using ciprofloxacin as a guide a very broad rule-of-thumb would be to separate the drug administration by about 2 hours to minimise this interaction. This is clearly not necessary with levofloxacin, lomefloxacin, moxifloxacin or ofloxacin, nor probably with some of the other qui-... 

Forster T, Blouin R. The effect of antacid timing on lomefloxacin bioavailability. Intersci Cc if Antimicrob Agents Chemother (1989) 29, 318. 

Shimada J, Shiba K, Oguma T, Miwa H, Yoshimura Y, Nishikawa T, Okabayashi Y, Kitagawa T, Yamamoto S. Effect of antacid on absorption of the quinolone lomefloxacin Anti-microb Agents Chemother (1992) 36,1219-24. 

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