Dear nmusers,
I have a set of steady state data for a parent drug and 2 metabolites
(maximum two observations/individual). the estimated volume of distribution
was massive greater than what is reported in literature. thus i tried to
build a $PRED steady state model as below. unfortunately it does not work.
could you please correct me !?
Regards
Mushnagi
$INPUT ID TIME DOSE RATE DV CMT EVID MDV SS COV1 COV2
$DATA Par2Met.txt IGNORE=#
$PRED
CLP=THETA(1)*EXP(ETA(1)) ; apparent clearance of the parent
FM1=THETA(2)*EXP(ETA(2)) ; formation clearance of first metabolite
CLM1=THETA(3)*EXP(ETA(3)) ; apparent clearance of the first metabolite
FM2=THETA(4)*EXP(ETA(4)) ; formation clearance of second metabolite
CLM2=THETA(5)*EXP(ETA(5)); apparent clearance of the second metabolite
CP=RATE/CLP
C4HO=CP*FM1/CLM1
C7HO=CP*FM2/CLM2
IF (CMT.EQ.2) Y=CP + EPS(1) ; parent
IF (CMT.EQ.3) Y=C4HO+ EPS(2) ; for first metabolite
IF (CMT.EQ.4) Y=C7HO + EPS(3) ; for second metabolite
$THETA
0.05
0.08
0.03
0.05
0.04
#ID TIME DOSE RATE DV CMT EVID MDV SS
1 12 80.4 80.36 0 1 1 1
1
1 12.01 80.4 0.00 1970 2 0 0
0
1 12.01 80.4 0.00 66 3 0 0
0
1 12.01 80.4 0.00 49 4 0 0
0
1 12.15 80.4 0.00 896 2 0 0
0
1 12.15 80.4 0.00 24 3 0 0
0
1 12.15 80.4 0.00 22 4 0 0
0