Re: Combined absorption model
Dear Galadriel:
You would need to provide an estimate of D2, the duration of zero-order input to CMT=2 in your model.
Sam Liao
Pharmax Research
> Dear all,
>
> I tried to build up a combined absorption model (zero order + first
> order)using ADVAN 4, following is the control file I found in the
> PDx-pop library,
>
> ...........
> CL=THETA(1)*EXP(ETA(1))
> V2=THETA(2)*EXP(ETA(2))
> Q =THETA(3)*EXP(ETA(3))
> V3=THETA(4)*EXP(ETA(4))
> KA=THETA(5)*EXP(ETA(5))
> R2=THETA(6)*EXP(ETA(6))
> F1=EXP(THETA(7)+ETA(7))/(1+EXP(THETA(7)+ETA(7)))
> F2=1-F1
> S2=V2
> .................
>
> and for each dose record, an additional IV adminstration dose record
> is inserted with same dosage & rate=-2
>
> ID TIME AMT DV CMT RATE........
> 1 0 100 . 1 0 .........
> 1 0 100 . 2 -2 .........
>
> An error message is reported 'PK PARAMETER FOR DURATION IS NOT
> SUPPLIED BY PK FOR COMPT. NO. 2'.
>
> So is it the proper way to code the data? How can I estimate combined
> absorption model without using the differiential equation?
>
> Many thanks for your help!
>
> BR,
> Galadriel