Aminoglycosides: The mixing of Piperacillin sodium and Tazobactam sodium injection with an aminoglycoside in vitro can result in substantial inactivation of the aminoglycoside.
When Piperacillin sodium and Tazobactam sodium injection was co-administered with tobramycin, the area under the curve, renal clearance, and urinary recovery of tobramycin were decreased by 11%, 32%, and 38%, respectively. The alterations in the pharmacokinetics of tobramycin when administered in combination with piperacillin/tazobactam may be due to in vivo and in vitro inactivation of tobramycin in the presence of piperacillin/tazobactam. The inactivation of aminoglycosides in the presence of penicillin-class drugs has been recognized. It has been postulated that penicillin-aminoglycoside complexes form; these complexes are microbiologically inactive and of unknown toxicity. In patients with severe renal dysfunction (i.e., chronic hemodialysis patients), the pharmacokinetics of tobramycin are significantly altered when tobramycin is administered in combination with piperacillin. The alteration of tobramycin pharmacokinetics and the potential toxicity of the penicillin-aminoglycoside complexes in patients with mild to moderate renal dysfunction which are occurring under circumstances where causal relationship to Piperacillin sodium and Tazobactam sodium injection is uncertain: Gastrointestinal: hepatitis, cholestatic jaundice.
Hematological: hemolyticanemia, anemia, thrombocytosis, agranulocytosis, pancytopenia.
Immune: hypersensitivity reactions, anaphylactic/anaphylactoid reactions (including shock).
Infections: candidal superinfections.
Renal: interstitial nephritis, renal failure.
Skin and Appendages: erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis.
Drug/Laboratory Test Interactions: As with other penicillin's, the administration of Piperacillin and tazobactam injection 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.