Calculation of Drug Concentration

Non-Uniform Multiple Oral Dose Regimen

A patient is started on a drug at an oral dose of 250 mg at time zero, 250 mg at 5 hours and 400 mg at 11 hours (makes no sense but a nice random regimen :- all times are from time zero). Using the data shown in the table below calculate the drug concentration at 24 hr after the first dose time. Assume a one compartment linear model applies to this drug in this concentration range.

Concentration versus Time after a Single 100 mg dose

Time (hr) Concentration (mg/L)

0 0

1 1.25

2 1.18

3 0.863

4 0.583

5 0.381

6 0.245

7 0.156

8 0.0993

9 0.063

10 0.04

11 0.0253

12 0.0161

13 0.0102

14 0.00646

15 0.00409

16 0.00259

17 0.00164

18 0.00104

19 0.00066

20 0.000419

21 0.000265

22 0.000168

23 0.000107

24 6.75E-5

Concentration versus Time after a Single 100 mg dose
Time (hr)	Concentration (mg/L)
0	0
1	1.25
2	1.18
3	0.863
4	0.583
5	0.381
6	0.245
7	0.156
8	0.0993
9	0.063
10	0.04
11	0.0253
12	0.0161
13	0.0102
14	0.00646
15	0.00409
16	0.00259
17	0.00164
18	0.00104
19	0.00066
20	0.000419
21	0.000265
22	0.000168
23	0.000107
24	6.75E-5

The equation:

Cp after non uniform multiple dose regimen

Equation 15.4.1 Drug Concentration during a Multiple Dose Regimen (Non-Uniform Regimen)

Last update: Sat 28 Nov 2015 04:52:06 pm

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