Yonex® for IV/IM Injection 150 mg: Each vial contains Colistimethate Sodium USP, equivalent to Colistin 150 mg or 4.5 million IU.

Colistimethate Sodium is a surface-active agent that penetrates and disrupts bacterial cell membranes. It exhibits bactericidal activity against aerobic gram-negative microorganisms such as Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa.

Yonex® is indicated for the treatment of acute or chronic infections caused by sensitive strains of certain gram-negative bacilli. It is particularly effective against infections caused by sensitive strains of Pseudomonas aeruginosa. This antibiotic is not effective against infections caused by Proteus or Neisseria. It has been clinically proven to treat infections due to the following gram-negative organisms: Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa.

Reconstitution

Reconstitute the 150 mg vial with 2.0 mL of sterile Water for Injection, USP.

The reconstituted solution contains Colistimethate Sodium at a concentration equivalent to 75 mg/mL of colistin base activity.

Gently swirl during reconstitution to avoid frothing.

Note: Inspect parenteral drug products visually for particulate matter and discoloration prior to administration. If such conditions are observed, do not use the product.

Adults and Pediatric Patients (IV or IM Administration): Administer Colistimethate Sodium in 2 to 4 divided doses, with a total daily dose of 2.5 to 5 mg/kg/day for patients with normal renal function, depending on the severity of the infection.

Obese Patients: Dosage should be based on ideal body weight.

Renal Impairment: Reduce the daily dose according to renal function (refer to the table below).

Intravenous Administration

Direct Intermittent Administration: Slowly inject half of the total daily dose over 3–5 minutes every 12 hours.

Continuous Infusion: Inject half of the daily dose over 3–5 minutes, then add the remaining half to an appropriate infusion solution (e.g., 0.9% NaCl, 5% dextrose). Administer the second half by slow IV infusion over 22–23 hours. Adjust the infusion rate based on renal function.

Note: Infusion solutions containing Colistimethate Sodium should be freshly prepared and used within 24 hours.

Yonex® is contraindicated in patients with a known hypersensitivity to Colistimethate Sodium or any of its components.

Maximum Daily Dose: Do not exceed 5 mg/kg/day in patients with normal renal function.

Neurological Disturbances: May include circumoral paresthesia, numbness, tingling, pruritus, vertigo, dizziness, and slurred speech. Patients should avoid driving or operating hazardous machinery during therapy. Dosage reduction may alleviate symptoms.

Nephrotoxicity: Reversible upon discontinuation. Monitor renal function closely.

Overdosage: May result in renal insufficiency, muscle weakness, apnea, or respiratory arrest.

Impaired renal function increases the risk of apnea.

Clostridium difficile-associated diarrhea (CDAD) has been reported, ranging from mild diarrhea to fatal colitis. Discontinue unnecessary antibiotics and manage CDAD appropriately.

Common side effects include:

Gastrointestinal: Upset stomach.

Neurological: Tingling of extremities and tongue, slurred speech, dizziness, vertigo, paresthesia.

Dermatological: Itching, urticaria, rash.

Other: Fever, increased BUN, elevated creatinine, decreased urine output, respiratory distress, apnea, nephrotoxicity.

Pregnancy: Category C. It is unknown if Colistimethate Sodium is excreted in human milk, though Colistin Sulfate is known to be excreted. Administer with caution to nursing women.

Safe for use in neonates, infants, children, and adolescents. Monitor pediatric patients closely as they may not report subjective symptoms of toxicity.

Avoid concomitant use with aminoglycosides and polymyxins unless absolutely necessary.

Curariform muscle relaxants, ether, succinylcholine, gallamine, and sodium cephalothin may enhance nephrotoxicity.

Symptoms include paresthesia, lethargy, confusion, ataxia, and respiratory arrest. Respiratory muscle paralysis may lead to death. Discontinue therapy and provide supportive care. The effectiveness of dialysis in overdose cases is unknown.

Store below 25°C in a dry place.

Protect from light and moisture.

Use reconstituted solution immediately or store in a refrigerator (2–8°C) for up to 24 hours.