Colistin

Restricted
C. diff Risk

Low

Oral Bioavailability

NA

Dosing

Dosing expressed in colistin base activityObese patients are dosed according to Dosing Body Weight (DBW).

Consult pharmacist or refer to "Additional Information" section for details.

CrCl ≥90 mL/minCrCl 80 to <90 mL/minCrCl 70 to <80 mL/minCrCl 60 to <70 mL/minCrCl 50 to <60 mL/minCrCl 40 to <50 mL/minCrCl 30 to <40 mL/minCrCl 20 to <30 mL/minCrCl 10 to <20 mL/minCrCl 5 to <10 mL/minCrCl 0 mL/minInitial Loading Dose: 300 mg IV load, then
Maintenance Dose: 180 mg IV Q12HInitial Loading Dose: 300 mg IV load, then
Maintenance Dose: 170 mg IV Q12HInitial Loading Dose: 300 mg IV load, then
Maintenance Dose: 150 mg IV Q12HInitial Loading Dose: 300 mg IV load, then
Maintenance Dose: 138 mg IV Q12HInitial Loading Dose: 300 mg IV load, then
Maintenance Dose: 122 mg IV Q12HInitial Loading Dose: 300 mg IV load, then
Maintenance Dose: 110 mg IV Q12HInitial Loading Dose: 300 mg IV load, then
Maintenance Dose: 98 mg IV Q12HInitial Loading Dose: 300 mg IV load, then
Maintenance Dose: 88 mg IV Q12HInitial Loading Dose: 300 mg IV load, then
Maintenance Dose: 80 mg IV Q12HInitial Loading Dose: 300 mg IV load, then
Maintenance Dose: 72 mg IV Q12HInitial Loading Dose: 300 mg IV load, then
Maintenance Dose: 65 mg IV Q12H

Post-dialysis supplemental dosesInitial Loading Dose: 300 mg IV load, then
Maintenance Dose: 65 mg IV Q12H3-hour IHD run

  • Supplement an additional 40 mg at end of dialysis run

4-hour IHD run

  • Supplement an additional 50 mg at end of dialysis run

Initial Loading Dose: 300 mg IV load, then
Maintenance Dose: 220 mg IV Q12H

Initial Loading Dose: 300 mg IV load, then
Maintenance Dose: 150-200 mg IV daily

General Information

Additional Information

Body weight calculation (kg)

ABW = Actual body weight
IBW = Ideal body weight

  • IBW (male) = 50.0 kg + [2.3 kg x (each inch greater 5 feet)]

  • IBW (female) = 45.5 kg + [2.3 kg x (each inch greater 5 feet)

DBW = dosing body weight

  • DBW = 0.4 x (ABW – IBW) + IBW

For “non-obese” patients use: ABW
For “obese” patients use: DBW

  • Consider “obese” if (ABW - IBW) / IBW is greater than 0.2

Creatinine clearance (mL/min)

CrCl (male) = [(140 – age) x weight x 60] / [50 x serum creatinine (umol/L)]

CrCl (female) = CrCl (male) x 0.85

Age is in years.

Weight (kg) = ABW if non-obese, or = DBW if obese

Common Usage

Infectious Diseases consultation recommended.

Pharmacology

Steady-State Plasma Concentration

  • The pharmacologic target for colistin is an average steady-state plasma concentration of 2 mg/L (Css,avg)

Susceptibility Breakpoint

  • The susceptibility breakpoint for colistin for Enterobacteriaceae, Pseudomonas aeruginosa, and Acinetobacter is less than or equal to 2 mg/L

Expressing Colistin Doses

  • Colistin doses in the scientific literature may be expressed in different ways. The conversion is as follows:

    • 1 million International Units of Colistin = 33 mg of Colistin Base Activity (CBA) = 80 mg of colistimethate (CMS)
  • All doses for Colistin should be expressed in Colistin Base Activity