Imipenem/Cilastatin Hikma Farmacêutica (Portugal) (Cilastatin, Imipenem)

Imipenem/Cilastatin is a broad‑spectrum carbapenem antibiotic used for serious bacterial infections in the hospital setting.

• Complicated intra‑abdominal infections: provides bacterial eradication within the abdominal cavity.
• Complicated urinary tract infections: eliminates resistant uropathogens causing upper and lower tract disease.
• Skin and soft tissue infections: treats deep‑seated or necrotizing infections caused by Gram‑negative and Gram‑positive bacteria.
• Nosocomial pneumonia: effective against ventilator‑associated and hospital‑acquired lung infections.
• Septicemia: rapidly clears bloodstream infections caused by susceptible organisms.

• 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 therapeutic plasma concentrations.

Common Side Effects

• Nausea: mild to moderate gastrointestinal upset.
• Vomiting: occasional emesis following infusion.
• Diarrhea: may range from loose stools to mild colitis.
• Headache: transient cranial discomfort.
• Infusion site reactions: erythema, pain, or phlebitis at the injection site.
• Elevated liver enzymes: transient increase in transaminases.

Serious or Rare Side Effects

• Seizures: especially in patients with renal impairment or CNS disorders.
• Anaphylaxis: acute, potentially life‑threatening hypersensitivity reaction.
• Clostridioides difficile colitis: severe antibiotic‑associated diarrhea.
• Renal toxicity: worsening kidney function in susceptible individuals.
• Severe hypersensitivity: Stevens‑Johnson syndrome or toxic epidermal necrolysis.
• Thrombocytopenia: marked reduction in platelet count.

Imipenem/Cilastatin should be used with careful clinical assessment and monitoring.

• Renal function monitoring: adjust dose in patients with impaired kidney function.
• Hypersensitivity caution: avoid in individuals with known allergy to carbapenems or β‑lactams.
• Seizure risk: use cautiously in patients with a history of CNS disorders.
• Superinfection vigilance: monitor for overgrowth of non‑susceptible organisms.
• Drug‑induced liver injury: assess liver enzymes during prolonged therapy.
• Store at 2-8°C: keep refrigerated, protect from light, do not freeze or shake.

Imipenem/Cilastatin may interact with several concomitant medicines.

Major Interactions (Avoid)

• Valproic acid: carbapenems reduce serum valproate levels, risking seizure breakthrough.
• Other carbapenems: concurrent use may increase toxicity without added benefit.
• Renal toxic agents (e.g., aminoglycosides): combined nephrotoxic potential.

Moderate Interactions (Monitor Closely)

• Diuretics: may enhance electrolyte disturbances.
• NSAIDs: can affect renal clearance, requiring dose adjustment.
• Anticoagulants (e.g., warfarin): monitor INR as antibiotic therapy may alter coagulation parameters.