Metabolite inhibition model

Dear All, I am working on lidocaine PK data from 106 patients receiving infusion for 48 hours. The metabolite (MEGX) will decrease the clearance of the parent drug (lidocaine). Therefore, I analyzed the data with nonlinear PK model (ADVAN6 TOL=3). I am wondering whether there is any metabolite inhibition model to analyze the lidocaine PK. Any comment or suggestion will be highly appreciated. Yung-Wei Hsu Mackay Memorial Hospital Taipei, Taiwan +++++++++++++++++ $SUBROUTINE ADVAN6 TOL=3 $MODEL COMP (ONE) COMP (TWO) $PK V1= THETA(1)*EXP(ETA(1)) VMAX=THETA(2)*EXP(ETA(2)) KM=THETA(3)*EXP(ETA(3)) V2= THETA(4)*EXP(ETA(4)) Q2=THETA(5)*EXP(ETA(5)) $DES DC1=A(1)/V1 DC2=A(2)/V2 CL=VMAX*DC1/(KM+DC1) DADT(1)=Q2*DC2−(Q2+ CL)*DC1 DADT(2)=Q2*(DC1−DC2) $ERROR C1=A(1)/V1 Y=C1*(1+ERR(1)) IPRED=Y ++++++++++++++++++++++++++++++++++++++++++ ------------ This message has been scanned for viruses and dangerous content.