Kolneb (Colistimethate Sodium)

Kolneb, a polymyxin antibiotic, is indicated for serious infections caused by Gram‑negative organisms.

• Pseudomonas aeruginosa infections: eradication of the pathogen and resolution of infection symptoms.
• Complicated urinary tract infections: clearance of bacterial load and symptom relief.
• Hospital‑acquired respiratory infections: reduction of pulmonary bacterial burden and improvement of breathing function.
• Skin and soft‑tissue infections due to Gram‑negative bacteria: elimination of infection and promotion of wound healing.

• Colistimethate Sodium binds to the lipopolysaccharide layer of the bacterial outer membrane, displacing calcium and magnesium ions. This interaction disrupts membrane integrity, increasing permeability and causing leakage of intracellular contents, which leads to rapid bacterial cell death, particularly against Gram‑negative organisms.

Adverse reactions may occur with colistimethate sodium therapy.

Common Side Effects

• Nausea: mild to moderate stomach upset.
• Diarrhea: increased bowel movements, sometimes watery.
• Rash: localized skin irritation or erythema.
• Elevated serum creatinine: early sign of renal stress.
• Headache: transient discomfort.

Serious or Rare Side Effects

• Nephrotoxicity: acute kidney injury requiring monitoring.
• Neurotoxicity: paresthesia, dizziness, or seizures.
• Anaphylaxis: severe allergic reaction with airway compromise.
• Respiratory failure: rapid decline in breathing function.
• Hematuria: blood in urine indicating renal involvement.
• Severe skin reactions: Stevens‑Johnson syndrome or toxic epidermal necrolysis.

Colistimethate sodium requires careful monitoring and specific safety measures.

• Renal function monitoring: assess baseline creatinine and repeat during therapy.
• Neurotoxicity monitoring: watch for tingling, numbness, or seizures.
• Hypersensitivity avoidance: discontinue if allergic reactions develop.
• Pregnancy and lactation caution: use only if benefits outweigh potential risks.
• Concomitant nephrotoxic drugs: avoid or adjust dosing when combined.
• Store at room temperature: keep in original packaging, protect from moisture and direct sunlight.

Colistimethate sodium can interact with other medications, affecting safety and efficacy.

Major Interactions (Avoid)

• Aminoglycosides: combined use markedly increases risk of nephrotoxicity.
• Loop diuretics: may exacerbate renal impairment when given together.

Moderate Interactions (Monitor Closely)

• Non‑steroidal anti‑inflammatory drugs (NSAIDs): potential additive renal stress.
• Vancomycin: may increase overall nephrotoxic burden.
• Cimetidine: could raise colistimethate plasma concentrations.
• Proton pump inhibitors: monitor for altered absorption.