hat cephalosporins may potentiate the adverse renal effects of nephrotoxic agents, such as aminoglycosides and loop diuretics. Carefully monitor renal function, especially during prolonged therapy or use of high aminoglycoside doses. The majority of reported cases involve the combination of aminoglycosides and cephalothin or cephaloridine, which are associated with dose-related nephrotoxicity as singular agents. Limited but conflicting data with other cephalosporins have been noted.
Mycophenolate: Drugs that alter the gastrointestinal flora may interact with mycophenolate by disrupting enterohepatic recirculation. Cefuroxime may decrease normal GI flora levels and thus lead to less free mycophenolate available for absorption.
Nizatidine: Avoid the concomitant use of H2-blockers and cefuroxime. Drugs that reduce gastric acidity, such as H2-blockers, can interfere with the oral absorption of cefuroxime axetil and may result in reduced antibiotic efficacy.
Omeprazole: Avoid the concomitant use of proton pump inhibitors (PPIs) and cefuroxime. Drugs that reduce gastric acidity, such as PPIs, can interfere with the oral absorption of cefuroxime axetil and may result in reduced antibiotic efficacy.
Omeprazole; Sodium Bicarbonate: Avoid the concomitant use of proton pump inhibitors (PPIs) and cefuroxime. Drugs that reduce gastric acidity, such as PPIs, can interfere with the oral absorption of cefuroxime axetil and may result in reduced antibiotic efficacy. Antacids can interfere with the oral absorption of cefuroxime axetil and may result in reduced antibiotic efficacy. If an antacid must be used while a patient is taking cefuroxime, administer the oral dosage of cefuroxime at least 1 hour before or 2 hours after the antacid.
Oral Contraceptives: It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception du |