RONAK

Colisma®

Generic name: Colistimethate sodium

Dosage form: Lyophilized powder containing 1 million and 4.5 million units for preparation of injectable solution

Drug class: Antibiotic

Indications: This medicine is used to treat acute or chronic infections caused by susceptible strains of certain Gram-negative microorganisms.

Colisma® is an inactive prodrug that is converted in the body to colistin. Colistin damages the bacterial cytoplasmic membrane, causing leakage of intracellular materials and ultimately death of the pathogen.

Treatment of acute and chronic infections caused by susceptible strains of Gram-negative bacilli, such as Pseudomonas aeruginosa, Enterobacter aerogenes, Escherichia coli, and Klebsiella pneumoniae, especially when resistant to other antibiotics or in patients who cannot use other antibiotics.

  • Cystic fibrosis
  • Prevention of bronchiectasis exacerbation

Lyophilized powder containing 1 million and 4.5 million units of Colistimethate sodium for preparation of injectable solution.

Colisma® 1 million units: Add 1 mL of sterile water for injection to the vial contents and dissolve the powder completely. The resulting solution contains 34 mg/mL Colistimethate sodium.

Colisma® 4.5 million units: Add 2 mL of sterile water for injection to the vial contents and dissolve the powder completely. The resulting solution contains 75 mg/mL Colistimethate sodium.

After adding sterile water for injection, gently rotate the vial to avoid foaming. Inspect the solution before use for suspended particles or discoloration.

Do not use the medicine if particles or discoloration are present.

If dilution is required, Colisma® is compatible with:

  • 0.9% sodium chloride
  • 5% dextrose
  • 5% dextrose with 0.9% sodium chloride
  • 5% dextrose with 0.45% sodium chloride
  • 5% dextrose with 0.225% sodium chloride
  • Lactated Ringer’s solution

Colisma® may be administered intravenously or intramuscularly, including into large muscles such as the gluteal muscle or the lateral thigh.

Intravenous administration may be performed as follows:

  • Direct injection: Slowly inject half of the daily dose over 3 to 5 minutes every 12 hours.
  • Direct injection and infusion: Administer half of the daily dose over 3 to 5 minutes, and administer the remaining half after dilution in compatible solutions as a slow infusion over 22 to 23 hours or longer.
  • Blood colistin level
  • Serum creatinine and urea levels
  • Urine output
  • Signs of neurotoxicity

Hypersensitivity to Colistimethate, colistin, or any component of the formulation.

  • Depending on dose, Colisma® may cause kidney toxicity. It should be used cautiously in patients with kidney impairment, and the dose must be adjusted according to the degree of impairment and the patient’s age.
  • Symptoms such as tingling or numbness around the mouth, hands, or feet, itching, dizziness, or speech disturbance may occur. Dose reduction usually improves these symptoms. If they occur, avoid activities requiring high alertness, such as driving or operating heavy machinery.
  • Long-term use of Colisma® may increase the risk of diarrhea caused by Clostridioides difficile. Contact your physician immediately if symptoms occur, such as stomach pain, very loose or watery stool, or bloody stool.

Consult your physician before using Colisma® during pregnancy or breastfeeding.

Colistin, the active form of Colistimethate sodium, is excreted in breast milk; therefore, breastfeeding should be done cautiously and under specialist medical supervision.

Like all medicines, Colisma® may cause unwanted side effects, although not everyone experiences them. More common possible side effects include:

  • Decreased urine volume
  • Dizziness
  • Fever
  • Skin rash, urticaria, and itching

Consult your physician or pharmacist about using Colisma® together with other medicines or supplements.

Each 1-million-unit package contains 10 vials of Colisma®.

Each 4.5-million-unit package contains 2 vials of Colisma®.

  • Store below 30°C, protected from light and moisture.
  • The medicine may be used until the end of the month stated in the expiry date on the package. Do not use or store expired medicines.
  • Keep the medicine out of the reach of children.
  • Keep the medicine in its original packaging until use.
  1. Colistin / Colistimethate: Drug information, UpToDate 2025
  2. Medicines.org.uk product information for Colistimethate sodium.