Azithromycin Antacids

Owing to interference by antacids, azithromycin should be given at least 1 hour before or 2 hours after antacids. Antacids containing aluminium and magnesium reduce peak serum concentrations, but the total extent of azithromycin absorption is not altered (45). 

Azithromycin 1 0 mg/kg x 1 day, 5 mg/kg per day x 4 days 10 mg/kg per day x 3 days or 30 mg/kg single dose (adult dose 500 mg x 1,250 mg x 4 days 500 mg/day x 3 days) Nausea, vomiting, diarrhea, abdominal pain S3 Separate from Al or Mg antacids by 2 hours diarrhea/vomiting more common with singledose regimen 3- or 5-day courses preferred increasing pneumococcal resistance many failures with H. influenzae infection... 

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. 

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. 

CEFPODOXIME, CEFUROXIME ANTACIDS L levels of these antibiotics L absorption Take azithromycin at least 1 hour before or 2 hours after an antacid. Take these cephalosporins at least 2 hours after an antacid. Separate quinolones and antacids by 2-6 hours. Separate tetracyclines and antacids by 2-3 hours... 

Studies of the concomitant use of azithromycin with carbamazepine, terfenadine, and zidovudine have not reported drug interactions [131-133]. With the potential exception of antacids, no drug interactions have been reported with azithromycin, which does not appear to be metabolized by the cytochrome P-450 system [4, 134], Both azithromycin and clarithromycin have been associated with digoxin toxicity. The postulated mechanism is by eradication of Eubacterium lentum, an anaerobic gram-positive bacteria responsible for the metabolism of digoxin in some patients [43]. 

In 10 healthy subjects the peak serum levels, but not the total absorption, of azithromycin was reduced by 30 mL Maalox (alimiinium/magnesi-um hydroxide). It is suggested therefore that azithromycin should not be given at the same time as antacids, but should be taken at least 1 hour... 

Foulds G, Hilligoss DM, Henry EB, Gerber N The effects of an antacid or cimetidine on the serum concentrations of azithromycin. /CfiwP armaco/(1991)31,164-7. 

Aluminium/magnesium hydroxide antacids may reduce the peak levels of azithromycin. Mylanta can prolong the absorption of erythromycin, but this is unlikely to be clinically important Aluminium/magnesium hydroxide antacids do not appear to significantly alter the pharmacokinetics of clarithromycin, roxithromycin or telithromycin. 

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