After an oral ampicillin dose of 500 mg the following conc were obtained:
- at time 0 hrconc 0 mg/L
- at time 1.0 hrconc 18 mg/L
- at time 2.0 hrconc 14 mg/L
- at time 4.0 hrconc 5 mg/L
- at time 6.0 hrconc 1.6 mg/L
Calculate ampicillin AUC using the trapezoidal rule (ampicillin t1/2 is 1.2 hr)
0,0
1
1,18
2
2,14
3
4,5
4
6,1.6
tail
The area of a trapezoid =
(0+18
2 )
.(1-0) = 9 mg-hr/L +
(18+14
2 )
.(2-1) = 16 mg-hr/L +
( 14+5
2 )
.(4-2) = 19 mg-hr/L +
( 5+1.6
2 )
.(6-4) = 6.6 mg-hr/L +
tail =
(1.6
0.693/1.2)
= 2.77 mg-hr/L +
