# PHAR 4634 Pharmaceutics III Chapter 6

## Homework Assignment - 1995 #3

1. Assuming a one compartment linear pharmacokinetic model, with kel = 0.16 hr-1; and V = 16.2 L, calculate the plasma concentration at 0.5, 1, 2, 3, 4, 6, 9, and 12 hours after starting a 200 mg/hr i.v. infusion of 3 hours duration. Plot the data on linear and semi-log graph paper.

2. Given the data in Table, calculate kel, and V. Assume a one compartment linear model.

 Time Since Start of Infusion (hr) Concentration (mg/L) 0.5 4.37 1 6.27 2 4.79 3 4.37 6 2.3

3. A given drug follows linear one compartment pharmacokinetics. If the drug half-life is 7 hr and the apparent volume of distribution is 25 L, calculate the i.v. infusion necessary to achieve a steady state concentration of 25 mg/L (1). What i.v. bolus loading dose would you use to achieve 25 mg/L more rapidly (2)? What rapid i.v. infusion rate would you need to get to 25 mg/L in 30 minute (3)? Describe all three dosing regimen and sketch (not graph) the three plasma concentration versus time profiles.