Tazocin Drug Interactions

As with other penicillins, concurrent administration of probenecid and piperacillin/tazobactam produced a longer half-life and lower renal clearance for both piperacillin and tazobactam. However, peak plasma concentrations of either drug are unaffected. No pharmacokinetic interaction is found between Tazocin and either vancomycin or tobramycin.
Compatibility of piperacillin/tazobactam with other aminoglycosides has not been established. Only the concentration and diluents for amikacin and gentamicin with the dosages of piperacillin/tazobactam listed in the table have been established as compatible for co-administration via y-site infusion.
Simultaneous co-administration via y-site in any manner other than listed previously may result in inactivation of the aminoglycoside by piperacillin/tazobactam.
During simultaneous administration of heparin, oral anticoagulants and other drugs which may affect the blood coagulation system, including thrombocyte function, appropriate coagulation tests should be performed more frequently and monitored regularly.
Piperacillin when used concomitantly with vecuronium has been implicated in the prolongation of the neuromuscular blockade of vecuronium. Due to their similar mechanism of action, it is expected that the neuromuscular blockade produced by any of the nondepolarizing muscle relaxants could be prolonged in the presence of piperacillin.
Piperacillin may reduce the excretion of methotrexate; therefore, serum levels of methotrexate should be monitored in patients to avoid drug toxicity.
Interference with Laboratory and Other Diagnostic Tests: As with other penicillins, the administration of piperacillin/tazobactam may result in a false-positive reaction for glucose in the urine using a copper-reduction method. It is recommended that glucose tests based on enzymatic glucose oxidase reactions be used.
There have been reports of positive test results using the Bio-Rad Laboratories Platelia Aspergillus EIA test in patients receiving piperacillin/tazobactam injection who were subsequently found to be free of Aspergillus infection. Cross-reactions with non-Aspergillus polysaccharides and polyfuranoses with Bio-Rad Laboratories Platelia Aspergillus EIA test have been reported. Therefore, positive test results in patients receiving piperacillin/tazobactam should be interpreted cautiously and confirmed by other diagnostic methods.