Imipenem/Cilastatine Steriscience (Cilastatin, Imipenem)

Imipenem/Cilastatin is a carbapenem antibiotic used to treat severe bacterial infections affecting various organ systems.

• Complicated intra‑abdominal infections: achieves rapid bacterial eradication in the peritoneal cavity and reduces postoperative complications.
• Complicated urinary tract infections: provides effective coverage of resistant Gram‑negative pathogens in the urinary tract.
• Skin and soft‑tissue infections: eliminates mixed aerobic and anaerobic organisms in deep tissue infections.
• Hospital‑acquired and ventilator‑associated pneumonia: delivers high lung tissue concentrations to treat resistant pneumonia.
• Severe sepsis: offers broad‑spectrum bactericidal activity essential for systemic infection control.

• Imipenem exerts its antibacterial effect by binding to penicillin‑binding proteins, inhibiting the final stages of peptidoglycan cross‑linking and thereby disrupting bacterial cell‑wall synthesis. Cilastatin, co‑administered, blocks renal dehydropeptidase I, preventing enzymatic degradation of imipenem in the kidneys and extending its plasma half‑life, which enhances and sustains the antimicrobial activity. The combined formulation therefore maintains therapeutic concentrations in plasma and tissues, allowing effective treatment of multidrug‑resistant organisms.

Imipenem/Cilastatin may cause a range of adverse reactions, varying from mild to severe.

Common Side Effects

• Nausea: mild gastrointestinal upset occurring in many patients.
• Diarrhea: loose stools, sometimes leading to dehydration.
• Vomiting: occasional emesis after infusion.
• Rash: skin erythema or pruritus.
• Headache: transient headache during therapy.
• Elevated liver enzymes: mild transaminase increases.

Serious or Rare Side Effects

• Seizures: risk increased in patients with renal impairment or CNS disorders.
• Anaphylaxis: severe allergic reaction requiring immediate discontinuation.
• Clostridioides difficile colitis: antibiotic‑associated severe diarrhea.
• Renal toxicity: acute kidney injury especially with concomitant nephrotoxic drugs.
• Thrombophlebitis: inflammation at the intravenous site.
• Severe hypersensitivity reactions: including Stevens‑Johnson syndrome.

Before initiating Imipenem/Cilastatin, clinicians should consider several safety measures to minimize risks.

• Assess renal function: adjust dosing or avoid use in severe renal impairment.
• Monitor for seizures: especially in patients with a history of CNS disease.
• Check for hypersensitivity: discontinue if rash, urticaria, or anaphylaxis develop.
• Avoid concomitant valproic acid: may reduce valproate plasma levels and precipitate seizures.
• Use aseptic technique: ensure sterile preparation and administration to prevent infection.
• Store at below 25°C: keep in the original container, protect from moisture and light.

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

Major Interactions (Avoid)

• Valproic acid: co‑administration markedly reduces valproate concentrations, risking seizure breakthrough.
• CNS depressants (e.g., phenobarbital, carbamazepine): may lower seizure threshold when combined with imipenem.
• Probenecid: can increase imipenem plasma levels, raising toxicity risk.

Moderate Interactions (Monitor Closely)

• Diuretics (e.g., furosemide): may enhance nephrotoxic potential; monitor renal function.
• Anticoagulants (e.g., warfarin): imipenem may alter INR; check coagulation parameters.
• Other nephrotoxic agents (e.g., aminoglycosides): increase risk of kidney injury; adjust dosing as needed.