Re: Generating Cmax at end of infusion

Hi Paul, You cannot use T in ADVAN3. ADVAN3 uses the exact solution to advance between TIME points. If you include the end of infusion as EVID=2 time point, you can get it there. Otherwise, I am not sure how to get hold on the solution at that specific time. It could be possible, because the end-of infusion should be (at least internally) the point to which the system is advanced, but I do not know how to get data at that (internal) point. An easier way would be to rewrite the system in differential equations (ADVAN6). Then you can get the solution at any time point T (in he $DES block) but you will have to output it on the next TIME point. Hope this helps Leonid -------------------------------------- Leonid Gibiansky, Ph.D. President, QuantPharm LLC web: www.quantpharm.com e-mail: LGibiansky at quantpharm.com tel: (301) 767 5566 Paul Hutson wrote: > G'day. > > I would like to generate a concentration at the end of an infusion of duration DUR. I am using ADVAN3 TRANS4 with log transformed data. Here is what I have tried, but I am getting an error that the parameter 'T' that I understood to be the machine time is undefined. Can anyone suggest a proper way to give set Cmax=exp(Y) at the end of the infusion of length DUR? > > Many thanks in advance. > Paul > $PK > ... > TT=TIME > > $ERROR > ;I've also tried > ;TT=TIME > ;TT=T > IPRE=F > EDV=EXP(DV) > W=1 > IF(F.GT.0) W=F > IRES=F-EDV > IWRE=IRES/W > LOGF=LOG(0.0001) > IF (F.GT.0) LOGF=LOG(F) > Y=LOGF+EPS(1) > ;GENERATE CMAX AT END OF INFUSION (DUR) > IF(DUR.EQ.TT) CMAX=EXP(Y) > -- > > Paul R. Hutson, Pharm.D. > > Associate Professor > > UW School of Pharmacy > > 777 Highland Avenue > > Madison WI 53705-2222 > > Tel 608.263.2496 > > Fax 608.265.5421 > > Pager 608.265.7000, p7856