Imipenem/Cilastatin Atb (Cilastatin Sodium, Imipenem Monohydrate)

Imipenem/Cilastatin is used to treat serious bacterial infections by inhibiting cell‑wall synthesis across a broad spectrum of pathogens.

• Complicated intra‑abdominal infections: provides rapid bacterial eradication and clinical cure.
• Complicated urinary tract infections: achieves high urinary concentrations and resolves infection.
• Skin and soft‑tissue infections: penetrates tissue to eliminate pathogenic bacteria.
• Community‑acquired and hospital‑acquired pneumonia: covers typical and resistant respiratory pathogens.
• Febrile neutropenia: offers broad‑spectrum coverage for high‑risk patients.

• Imipenem binds to multiple penicillin‑binding proteins, blocking the final stages of bacterial cell‑wall peptidoglycan cross‑linking, which leads to cell lysis. Cilastatin inhibits renal dehydropeptidase I, preventing enzymatic degradation of imipenem and thereby maintaining therapeutic plasma and urinary concentrations.

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

Common Side Effects

• Nausea: mild to moderate gastrointestinal upset.
• Vomiting: occasional emesis during therapy.
• Diarrhea: loose stools, may be self‑limiting.
• Rash: mild skin erythema or pruritus.
• Headache: transient cranial discomfort.
• Elevated liver enzymes: transient increase in ALT/AST.

Serious or Rare Side Effects

• Seizures: especially in patients with CNS disorders or high doses.
• Anaphylaxis: acute hypersensitivity requiring immediate discontinuation.
• Clostridioides difficile‑associated diarrhea: severe colitis risk.
• Nephrotoxicity: impaired renal function in susceptible individuals.
• Stevens‑Johnson syndrome or toxic epidermal necrolysis: severe skin reactions.
• Eosinophilic lung disease: rare pulmonary infiltrates with eosinophilia.

Before initiating Imipenem/Cilastatin therapy, clinicians should consider several precautionary measures.

• Assess renal function: adjust dose based on creatinine clearance.
• Monitor for seizures: avoid in patients with a history of epilepsy or high‑dose therapy.
• Evaluate for hypersensitivity: discontinue if rash, angioedema, or anaphylaxis occurs.
• Use with caution in patients with a history of seizures or CNS disorders.
• Adjust dose in renal impairment: follow recommended dosing guidelines.
• Store at 2-8°C: keep refrigerated, protect from light, do not freeze.

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

Major Interactions (Avoid)

• Valproic acid: reduces seizure control and may precipitate breakthrough seizures.
• Other carbapenems: additive neurotoxicity risk, especially seizures.
• Probenecid: may increase plasma concentrations, requiring monitoring.

Moderate Interactions (Monitor Closely)

• Warfarin: monitor INR for potential anticoagulant effect alteration.
• Diuretics: watch electrolytes and renal function for additive nephrotoxicity.
• Rifampin: may lower imipenem levels, reducing efficacy.
• NSAIDs: increase risk of renal impairment.
• Aminoglycosides: monitor for synergistic nephrotoxic effects.