Calculation of Drug Concentration

Non-Uniform Multiple Oral Dose Regimen

A patient is started on a drug at an oral dose of 100 mg at time zero, 500 mg at 2 hours and 300 mg at 4 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 7.3

2 7.32

3 6.08

4 4.84

5 3.81

6 2.99

7 2.34

8 1.84

9 1.44

10 1.13

11 0.883

12 0.692

13 0.542

14 0.425

15 0.333

16 0.261

17 0.204

18 0.16

19 0.125

20 0.0983

21 0.077

22 0.0603

23 0.0473

24 0.037

Concentration versus Time after a Single 100 mg dose
Time (hr)	Concentration (mg/L)
0	0
1	7.3
2	7.32
3	6.08
4	4.84
5	3.81
6	2.99
7	2.34
8	1.84
9	1.44
10	1.13
11	0.883
12	0.692
13	0.542
14	0.425
15	0.333
16	0.261
17	0.204
18	0.16
19	0.125
20	0.0983
21	0.077
22	0.0603
23	0.0473
24	0.037

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 27 Jul 2024 08:10:08 pm

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