4Comp.mod.

From: "Ralph Quadflieg" <quadflieg@uni-bonn.de> Subject: 4Comp.mod. Date: 28 Sep 1998 14:16:27 -0400 Dear NONMEM users, I am a new NONMEM user and I have some difficulties in writing a control file for my pk problem: I would like to model 3 data sets (3 different settings) with a 4 compartment model (depot, central, peripher1, peripher2). a) the depot comp. should be the dosing compartment with a first order process to the central comp. (is not known) a bioavailability factor (is not known, oral appl.) and a lagtime parameter (is not known) b) the central comp. should be the dosing comp. with two different constant rates (are known) and a bioavailability factor = 1 (iv infusion) I thought that this should be a problem for ADVAN6 and TRANS1 with a MODEL record like this: MODEL NCOMPARTMENTS = 4 COMP = (DEPOT) COMP = (CENTRAL, DEFOBS) COMP = (PER1) COMP = (PER2) LINK DEPOT TO CENTRAL = 1 LINK CENTRAL AND PER1 = 3 LINK CENTRAL AND PER2 = 5 LINK CENTRAL TO OUTPUT = 7 PK KA = THETA(1) * EXP(ETA(1)) V2 = THETA(2) * EXP(ETA(2)) CL23 = THETA(3) * EXP(ETA(3)) V3 = THETA(4) * EXP(ETA(4)) CL24 = THETA(5) * EXP(ETA(5)) V4 = THETA(6) * EXP(ETA(6)) CL20 = THETA(7) * EXP(ETA(7)) F1 = THETA(8) * EXP(ETA(8)) ALAG1 = THETA(9) * EXP(ETA(9)) S1 = V1 k23 = CL23/V2 k32 = CL23/V3 k24 = CL24/V2 k42 = CL24/V4 k20 = CL20/V2 and a corresponding data file with RATE CMT EVID PCMT data items. But there are problems due to the MODEL block, which I cannot solve (especially the LINK statement). I am a bit confused about the different possibilities of working with the LINK statements within the MODEL block or within th PK block, I should say. The MODEL is established with differential equations, but with this control file the run takes a lot of time. (around one hour). I would be pleased if there was somebody who can help me. Thank you in advance Ralph Quadflieg Dept.Pharm.Techn.Biopharm. University of Bonn An der Immenburg 4 D-53121 Bonn Germany quadflieg@uni-bonn http://www.pharma.uni-bonn.de/pharmtech/ Tel.: ++49 228 218997 Fax.:++49 228 735268