Imipenem/Cilastatin Kabi (Cilastatin Sodium, Imipenem Monohydrate)

Imipenem/Cilastatin is a carbapenem antibiotic used for serious bacterial infections affecting various organ systems.

• Complicated intra‑abdominal infections: provides broad‑spectrum coverage to eradicate Gram‑negative, Gram‑positive and anaerobic pathogens.
• Complicated urinary tract infections: eliminates resistant uropathogens causing pyelonephritis and cystitis.
• Nosocomial pneumonia: treats hospital‑acquired and ventilator‑associated pneumonia caused by multidrug‑resistant organisms.
• Severe skin and soft‑tissue infections: resolves infections such as cellulitis and necrotizing fasciitis.
• Sepsis and septic shock: offers rapid bacterial clearance in systemic infections.

• Imipenem binds to penicillin‑binding proteins, inhibiting bacterial cell‑wall synthesis and causing cell lysis. Cilastatin co‑administered inhibits renal dehydropeptidase I, preventing enzymatic degradation of imipenem, thereby maintaining therapeutic plasma concentrations and extending antibacterial activity against a wide range of Gram‑negative, Gram‑positive and anaerobic organisms, including many resistant strains.

Adverse reactions to Imipenem/Cilastatin may vary in frequency and severity.

Common Side Effects

• Nausea: mild gastrointestinal discomfort.
• Diarrhea: loose, sometimes watery stools.
• Rash: mild skin erythema or pruritus.
• Elevated liver enzymes: transient increase in ALT/AST.
• Injection site pain: discomfort at the IV site.

Serious or Rare Side Effects

• Seizures: central nervous system excitation, especially in renal impairment.
• Anaphylaxis: severe allergic reaction with hives, airway swelling.
• Stevens‑Johnson syndrome: rare mucocutaneous blistering.
• Clostridioides difficile colitis: severe diarrhea due to gut flora disruption.
• Renal dysfunction: worsening kidney function in susceptible patients.

Before initiating Imipenem/Cilastatin therapy, clinicians should consider several safety precautions.

• Renal function assessment: adjust dose in patients with impaired kidney function.
• History of seizures: avoid or monitor in individuals with prior seizure disorders.
• Allergy evaluation: confirm no known hypersensitivity to β‑lactam antibiotics.
• Concomitant valproic acid: monitor for reduced antiepileptic levels.
• Pregnancy and lactation: use only if potential benefit justifies potential risk.
• Store at 2‑8 °C: keep refrigerated, protect from light, do not freeze or shake.

Imipenem/Cilastatin can interact with other medicines, affecting efficacy or safety.

Major Interactions (Avoid)

• Valproic acid: reduces serum valproate concentrations, risking seizure breakthrough.
• Co‑administration with other β‑lactam antibiotics: may increase risk of additive toxicity.
• Renal dehydropeptidase inhibitors other than cilastatin: may cause excessive imipenem levels.

Moderate Interactions (Monitor Closely)

• Diuretics: may enhance nephrotoxic potential, monitor renal function.
• Probenecid: can decrease renal clearance of imipenem, adjust dose if needed.
• Anticoagulants (warfarin): monitor INR as infection may alter coagulation status.