Antacids drug interactions

Antacids also have clinically significant drug interactions with tetracycline, ferrous sulfate, isoniazid, quinidine, sul-fonylureas, and quinolone antibiotics. Antacid-drug interactions are influenced by antacid composition, dose, dosage schedule, and formulation. 

Adverse effects with the tetracyclines include gastrointestinal upset drug interactions with dairy products, antacids, and iron and phototoxicity. Minocycline can also cause vestibular complications (headache and dizziness) and skin discoloration that is not typical with tetracycline and doxycycline.16... 

Doxycycline 100 mg twice daily Avoid in children under 8 years Can cause photosensitivity, gastrointestinal problems, tooth staining in young children many drug-drug interactions (antacids, iron, calcium)... 

Chemical drug interactions result when two administered substances combine with each other chemically Tetracyclines complex with Ca (in milk), with aluminum (Al) and magnesium (Mg) (often components of antacids), and with Fe (in some multiple vitamins) to reduce the absorption of the tetracycline antibiotic. 

Azithromycin Drugs that may interact with azithromycin include antacids, cyclosporine, HMG-CoA reductase inhibitors, pimozide, tacrolimus, theophyllines, and warfarin. Also consider all drug interactions with erythromycin. 

Drugs that may interact with ribavirin capsules/oral solution include antacids. Drugs... 

All quinolones interact with multivalent cations, forming chelation complexes resulting in reduced absorption. Major offenders are antacids vitamins containing calcium and iron can also be problematic. All fluoroquinolones interact with warfarin, didanosine (ddi), and phenytoin, resulting in decreased absorption or metabolism. Ciprofloxacin and other second-generation drugs interact with theophylline by decreasing its clearance, which leads to theophylline toxicity. 

Certain drugs interact with BZs by altering their absorption. In addition to adding to CNS depression, ethanol increases the rate of absorption of BZs (Hobbs et ah, 1996). Conversely, antacids slow the absorption of BZs (Ballenger, 1995). 

Azithromycin is rapidly absorbed and well tolerated orally. It should be administered 1 hour before or 2 hours after meals. Aluminum and magnesium antacids do not alter bioavailability but delay absorption and reduce peak serum concentrations. Because it has a 15-member (not 14-member) lactone ring, azithromycin does not inactivate cytochrome P450 enzymes and therefore is free of the drug interactions that occur with erythromycin and clarithromycin. 

Drug Interactions Acyclovir Antacids with magnesium and aluminum hydroxides Cholestyramine Drugs that alter gastrointestinal flora may interact with mycophenolate mofetil by disrupting enterohepatic recirculation Probenecid... 

Drug Interactions Gemfibrozil Niacin Erythromycin Cholestyramine Digoxin Cimetidine/ranitidine/ omeprazole Rifampicin Warfarin Itraconazole Gemfibrozil Niacin Erythromycin Propranolol Digoxin Warfarin Antacids Colestipol Digoxin Erythromycin Oral contraceptives Fibrates Niacin Azole antifungals... 

Potential drug interactions include an increased AUC of zalcitabine when administered in combination with probenecid or cimetidine and decreased bioavailability when zalcitabine is coadministered with antacids or metoclopramide. Lamivudine inhibits the phosphorylation of zalcitabine in vitro, potentially interfering with its efficacy. 

Because drugs are often taken orally at the same time, the GI tract is a relatively common site for drug interactions to occur. Possible interactions during absorption include changes in local pH (e.g., antacids), altered gastric emptying and intestinal motility, and the formation of complexes. 

Drug interactions The effect of antacids and cations on the absorption of these agents was considered above. Ciprofloxacin, ofloxacin and enoxacin can increase the serum levels of theophylline by inhibiting its metabolism. They also may raise levels of warfarin, caffeine and cyclosporine. Cimetidine interferes with the... 

Drug Interaction Unlikely Unlikely Antacid-decrease effect Unlikely Unlikely... 

Cordoba-Diaz M, Cordoba-Borrego M, Cordoba-Diaz D. Influence of pharmacotechnical design on the interaction and availability of norfloxacin in directly compressed tablets with certain antacids. Drug Dev Ind Pharm 2000 26(2) 159-66. 

Sadowski DC. Drug interactions with antacids. Mechanisms and clinical significance. Drug Saf 1994 ll(6) 395-407. 

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