Imipenem/Cilastatin Aptapharma (Cilastatin, Imipenem Anhydrate)

Imipenem/cilastatin is a carbapenem antibiotic used to treat severe bacterial infections across several 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.
• Hospital‑acquired bacterial pneumonia: targets multidrug‑resistant organisms responsible for ventilator‑associated pneumonia.
• Skin and soft‑tissue infections: treats deep or necrotizing infections where other agents may fail.
• Severe sepsis and septic shock: offers rapid bactericidal activity in critically ill patients.

• Imipenem binds to penicillin‑binding proteins, inhibiting the final stages of bacterial cell‑wall synthesis and leading to cell lysis. Cilastatin, co‑administered, blocks renal dehydropeptidase I, preventing enzymatic degradation of imipenem and thereby maintaining therapeutic concentrations in the kidney and bloodstream.

Common Side Effects

• Nausea: mild to moderate gastrointestinal upset.
• Diarrhea: may be watery and self‑limiting.
• Rash: erythematous skin eruptions.
• Injection site reactions: pain, erythema, or swelling at the infusion site.

Serious or Rare Side Effects

• Seizures: especially in patients with pre‑existing CNS disorders or high plasma concentrations.
• Clostridioides difficile‑associated colitis: severe diarrhea with possible pseudomembranous colitis.
• Anaphylaxis: rapid onset of airway compromise, hypotension, and urticaria.
• Stevens‑Johnson syndrome/toxic epidermal necrolysis: extensive skin detachment and mucosal involvement.
• Renal toxicity: elevated serum creatinine or reduced urine output.

Before initiating therapy, clinicians should consider several safety measures.

• Renal function assessment: adjust dosing in patients with impaired clearance.
• Seizure risk evaluation: avoid in individuals with a history of epilepsy or CNS disease.
• Hypersensitivity screening: discontinue if signs of allergic reaction appear.
• Concomitant CNS depressants: use with caution as they may lower seizure threshold.
• Dose adjustment in renal impairment: follow established guidelines for reduced creatinine clearance.
• Store at below 25°C: keep in the original pack, protect from moisture and light.

Imipenem/cilastatin may interact with other medicines, requiring attention to avoid adverse outcomes.

Major Interactions (Avoid)

• Valproic acid: reduces valproate levels, risking seizure breakthrough.
• Probenecid: decreases renal clearance, increasing imipenem toxicity.
• Ganciclovir: carbapenems may diminish antiviral efficacy.

Moderate Interactions (Monitor Closely)

• Loop diuretics: heightened risk of nephrotoxicity.
• Non‑steroidal anti‑inflammatory drugs (NSAIDs): may exacerbate renal impairment.
• Warfarin: possible alteration of INR, requiring closer monitoring.