Imipenem/Cilastatine Fresenius Kabi (Cilastatin Sodium, Imipenem Monohydrate)

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

• Complicated intra‑abdominal infections: provides rapid bacterial clearance in severe abdominal sepsis.
• Complicated urinary tract infections: eradicates resistant uropathogens causing pyelonephritis.
• Skin and soft‑tissue infections: treats deep tissue infections caused by Gram‑negative and Gram‑positive bacteria.
• Hospital‑acquired and ventilator‑associated pneumonia: covers multidrug‑resistant respiratory pathogens.
• Meningitis: achieves therapeutic concentrations in cerebrospinal fluid for bacterial meningitis.
• Febrile neutropenia: offers empiric coverage for high‑risk neutropenic patients.

• Imipenem binds to penicillin‑binding proteins, inhibiting the final stages of bacterial cell‑wall peptidoglycan synthesis, which leads to cell lysis. Cilastatin, co‑administered, blocks renal dehydropeptidase I, preventing enzymatic degradation of imipenem and thereby maintaining its plasma concentration and antibacterial activity.

Adverse reactions may occur with any antimicrobial therapy and should be monitored.

Common Side Effects

• Nausea: mild to moderate gastrointestinal upset.
• Vomiting: occasional emesis following infusion.
• Diarrhea: may range from loose stools to mild colitis.
• Rash: skin erythema or pruritus.
• Headache: transient headache during or after infusion.
• Elevated liver enzymes: mild transaminase increase.

Serious or Rare Side Effects

• Seizures: especially in patients with renal impairment or CNS disorders.
• Anaphylaxis: severe hypersensitivity reaction requiring immediate intervention.
• Clostridioides difficile infection: antibiotic‑associated colitis.
• Severe neutropenia or thrombocytopenia: hematologic suppression.
• Renal toxicity: worsening renal function in susceptible individuals.
• Stevens‑Johnson syndrome: rare severe cutaneous adverse reaction.

Careful assessment and monitoring are required when using this injectable antibiotic.

• Renal function assessment: evaluate creatinine clearance before initiation and adjust dosing as needed.
• Monitor for seizures: observe patients with a history of CNS disease or electrolyte imbalance.
• Dose adjustment in renal impairment: reduce dose or extend interval based on renal function.
• Caution with concomitant nephrotoxic agents: avoid or closely monitor when used with other kidney‑toxic drugs.
• Avoid valproic acid co‑administration: imipenem reduces valproate levels, risking seizure breakthrough.
• Store at 2-8°C: keep refrigerated, protect from light, do not freeze or shake.

Imipenem/Cilastatin may interact with several drug classes, requiring vigilance.

Major Interactions (Avoid)

• Valproic acid: reduces serum valproate concentrations, increasing seizure risk.
• Other carbapenems: concurrent use may increase neurotoxicity.
• High‑dose aminoglycosides: additive nephrotoxicity.

Moderate Interactions (Monitor Closely)

• Diuretics: may potentiate electrolyte disturbances that lower seizure threshold.
• Warfarin: monitor INR as antibiotics can alter anticoagulant effect.
• Oral contraceptives: possible reduction in efficacy; advise alternative contraception.