Module 4. Effects of altered volume of distribution on plasma concentrations.


Having completed this exercise and based on pharmacokinetic constants and data, students should be able to:



Download vz.xlsx, the worksheet for this module. Depending on your settings, you may have to "enable editing" in order to make the changes suggested by the exercise.

Pharmacokinetic variables on the spreadsheet are preset for a typical adult horse (#1) and "typical" neonate (#2) given gentamicin.

Target Concentrations

Manipulate Dosage




Questions (Key)

  1. Estimate a dose of gentamicin would produce a Cmax in foals similar to that of adults dosed at 9.0 mg/kg. Assume a 24 hour dosing interval. (The number need not be exact. You may use the Excel worksheet for this purpose if you wish)
  2. Any potential for drug accumulation with repeated doses is reduced directly by:
  3. Defend this statement: "Dosing a foal as if it were an adult creates the risk of producing gentamicin toxicity without efficacy."