Mechanism of action-

Piperacillin is a penicillin beta-lactam antibiotic used in the treatment of bacterial infections caused by susceptible, usually gram-positive, organisms. By binding to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall, Piperacillin inhibits the third and last stage of bacterial cell wall synthesis. Cell lysis is then mediated by bacterial cell wall autolytic enzymes such as autolysins; it is possible that Piperacillin interferes with an autolysin inhibitor.

Tazobactam inhibits the action of bacterial beta-lactamase producing organisms, which are normally resistant to beta-lactam antibiotics. This augments the effects of antibiotics which would otherwise not be effective in treating certain infections. These antibiotics contain a beta-lactam ring in their chemical structure, which is destroyed by beta-lactam resistant organisms. When combined with other antibiotics, a variety of infections, including serious and life-threatening infections may be treated.

Pharmacokinetics-

Piperacillin:
Volume of distribution of piperacillin is 101 ml/kg. It is largely not metabolised and is eliminated primarily by glomerular filtration and tubular secretion; it is excreted rapidly as unchanged drug in high concentrations in the urine. Half-life of piperacilline is 36-72 min.

Tazobactam:
It is 30% bound to plasma protein and about 80% of the metabolites are excreted in urine.

Common side effects of the injection includes:

• Rash
• Vomiting
• Allergic reaction
• Nausea
• Diarrhea

This injection should not be used in the following conditions:

• Chronic kidney disease
• Seizures
• Increased risk of bleeding due to clotting disorder
• Low amount of potassium in the blood
• Diarrhea from an infection with Clostridium difficile bacteria

Following drugs may interact with the combinations:

• Antithrombin
• Argatroban
• BCG vaccine live
• Cholera vaccine
• Heparin
• Warfarin
• Azithromycin
• Chloramphenicol
• Clarithromycin
• Doxycycline
• Tetracycline
• Vancomycin