# Pharmaceutics III - PHAR 4634

## Homework #6

1. Assuming a two compartment linear pharmacokinetic model, with kel = 0.20 hr-1, k12 = 1.2 hr-1, k21 = 1.4 hr-1; and V = 43.8 L, calculate the plasma concentration at 0.25, 0.5, 1, 2, 4, 6, 8, 10, and 12 hours after 100 mg i.v. bolus dose. Plot the data on linear and semi-log graph paper.

2. The data shown at the right were collected after an iv bolus of 200 mg. Using the method of residuals calculate A, B, , and . Then calculate kel, k12, k21, Vc, and Varea.

Time (hr) Concentration (mg/L)
0.25 14.8
0.5 12.1
1 8.8
2 6.0
4 4.0
6 2.2
8 1.4
10 0.91
12 0.55

3. Given that b = 0.14 hr-1 and Varea = 32.8 L calculate an oral dosing regimen to achieve an average plasma concentration of 15 mg/L (Assume F = 0.85).

4. A drug was administered both IV (200 mg) and PO (500 mg) to the same subject. The AUC and AUMC from the IV data were 87.5 mg.hr.L-1 and 745 mg.hr2.L-1, respectively. The AUC and AUMC from the PO data were 116.74 mg.hr.L-1 and 1095 mg.hr2.L-1, respectively. Using non compartmental methods calculate all appropriate pharmacokinetic parameters.