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aspirin, buffered oral

Selected Oral Quinolones/Selected Oral Cations

This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.

Medical warning:

Moderate. These medicines may cause some risk when taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.

How the interaction occurs:

Your medicine contains aluminum, iron, lanthanum, magnesium, and/or zinc, which are cations that may bind to your antibiotic in your digestive tract. This prevents your body from absorbing the antibiotic.

What might happen:

The blood levels of your antibiotic may be decreased, which will decrease the effectiveness in treating your infection.

What you should do about this interaction:

You should time when you take your antibiotic and your other medicine so that you do not take: ---gatifloxacin for at least 4 hours before oral cations. ---gemifloxacin for at least 2 hours before or 3 ours after oral cations. ---lomefloxacin for at least 2 hours before or 4 hours after oral cations. ---moxifloxacin for at least 4 hours before or 8 hours after oral cations. ---trovafloxacin for at least 2 hours before or after oral cations.If you are taking lanthanum, your doctor may tell you to follow the above timing instructions or different ones, or your doctor may tell you to skip doses that you would normally take at the same time as your antibiotic.If you are not sure which antibiotic you are on, if you do not see your antibiotic listed, or if you have questions about the timing of doses of your medicine, contact your healthcare professionals (e.g. doctor or pharmacist). They may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.


1.Tequin (gatifloxacin) US prescribing information. Bristol-Myers Squibb Company January, 2006.
2.Factive (gemifloxacin mesylate) US prescribing information. Oscient Pharmaceuticals August, 2013.
3.Maxaquin (lomefloxacin hydrochloride) US prescribing information. Pfizer Inc. January, 2005.
4.Avelox (moxifloxacin hydrochloride) US prescribing information. Bayer Pharmaceuticals Corporation August, 2013.
5.Trovan (trovafloxacin mesylate) US prescribing information. Roerig April, 2000.
6.Fosrenol (lanthanum carbonate) US prescribing information. Shire US Inc. September, 2011.
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12.Allen A, Bygate E, Faessel H, Isaac L, Lewis A. The effect of ferrous sulphate and sucralfate on the bioavailability of oral gemifloxacin in healthy volunteers. Int J Antimicrob Agents 2000 Aug;15(4):283-9.
13.Lehto P, Kivisto KT. Different effects of products containing metal ions on the absorption of lomefloxacin. Clin Pharmacol Ther 1994 Nov; 56(5):477-82.
14.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. Antimicrob Agents Chemother 1992 Jun; 36(6):1219-24.
15.Stass H, Bottcher MF, Ochmann K. Evaluation of the influence of antacids and H2 antagonists on the absorption of moxifloxacin after oral administration of a 400mg dose to healthy volunteers. Clin Pharmacokinet 2001;40 Suppl 1:39-48.
16.Stass H, Kubitza D. Effects of iron supplements on the oral bioavailability of moxifloxacin, a novel 8-methoxyfluoroquinolone, in humans. Clin Pharmacokinet 2001;40 Suppl 1:57-62.
17.Stass H, Wandel C, Delesen H, Moller JG. Effect of calcium supplements on the oral bioavailability of moxifloxacin in healthy male volunteers. Clin Pharmacokinet 2001;40 Suppl 1:27-32.
18.Jaehde U, Sorgel F, Stephan U, Schunack W. Effect of an antacid containing magnesium and aluminum on absorption, metabolism, and mechanism of renal elimination of pefloxacin in humans. Antimicrob Agents Chemother 1994 May;38(5):1129-33.
19.Lazzaroni M, Imbimbo BP, Bargiggia S, Sangaletti O, Dal Bo L, Broccali G, Porro GB. Effects of magnesium-aluminum hydroxide antacid on absorption of rufloxacin. Antimicrob Agents Chemother 1993 Oct;37(10):2212-6.
20.Granneman GR, Stephan U, Birner B, Sorgel F, Mukherjee D. Effect of antacid medication on the pharmacokinetics of temafloxacin. Clin Pharmacokinet 1992;22 Suppl 1:83-9.
21.Minami R, Nakamura C, Inotsume N, Nakano M. Effects of aluminum hydroxide and famotidine on bioavailability of tosufloxacin in healthy volunteers. Antimicrob Agents Chemother 1998 Feb;42(2):453-5.
22.Teng R, Dogolo LC, Willavize SA, Friedman HL, Vincent J. Effect of Maalox and omeprazole on the bioavailability of trovafloxacin. J Antimicrob Chemother 1997 Jun;39 Suppl B:93-7.
23.Phansalkar S, van der Sijs H, Tucker AD, Desai AA, Bell DS, Teich JM, Middleton B, Bates DW. Drug-drug interactions that should be non-interruptive in order to reduce alert fatigue in electronic health records. J Am Med Inform Assoc 2012 Sep 25.

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