Colistin

C difficile risk
Low
Oral Bioavailability
N/A

Dosing

ALL DOSING IS FOR COLISTIN BASE

If patient is less than 60 kg300 mg IV loading dose, then 150 mg IV q12h (starting 12 hours after loading dose)Give 2.5 mg/kg IV Q12H

3 - 8mg/kg/day IV divided q8h (maximum 360 mg/day)

Nebulized (inhalation therapy): 150 mg Q12H

0 - 10 eGFR10 - 50 eGFR150 mg IV q48h, or if less than 60 kg, 2.5 mg/kg IV q48h150 mg IV q24h, or if less than 60 kg, 2.5 mg/kg IV q24h

General Information

Infections caused by multi-drug resistant gram negative organisms including carbapenemase-producing organisms.

Consultation with infectious disease is strongly recommended.

Pregnancy:

  • No data in human pregnancy.

  • Limited data in animal models do not suggest teratogenicity.

Breastfeeding:

  • Limited data indicate that colistin is minimally excreted into breastmilk following intramuscular administration of colistimethate.

  • Because colistin is poorly absorbed orally, it is unlikely to be absorbed in appreciable amounts by the infant or adversely affect the breastfed infant.

  • However, no studies have evaluated serum levels or adverse effects in breastfed infants whose mothers were receiving colistimethate.

  • Breastfeeding is acceptable with the use of inhaled colistin or colistimethate.

Serum creatinine, urine output

  • Nephrotoxicity

  • Neurotoxicity

  • Muscle weakness

  • Dizziness, paresthesias, slurred speech, vertigo

  • Concomitant use of nephrotoxic agents.

  • Can enhance the neuromuscular-blocking effect of neuromuscular-blocking agents.

Avoid in myasthenia gravis.

ALL DOSES FOR COLISTIN MUST BE EXPRESSED IN COLISTIN BASE.
Colistin Base Activity (CBA) 1 mg is defined to be equivalent to colistimethate sodium (CMS) 30,000 units which is equivalent to ~2.4 mg CMS.

Antimicrobial Class: Colistimethate (or the sodium salt [colistimethate sodium]) is the inactive prodrug that is hydrolyzed to colistin, which acts as a cationic detergent and damages the bacterial cytoplasmic membrane causing leaking of intracellular substances and cell death

ALL DOSES FOR COLISTIN MUST BE EXPRESSED IN COLISTIN BASE.
Colistin Base Activity (CBA) 1 mg is defined to be equivalent to colistimethate sodium (CMS) 30,000 units which is equivalent to ~2.4 mg CMS.