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Re: [NMusers] Why should we avoid using micro rate constants?

From: Leonid Gibiansky <>
Date: Sun, 3 Feb 2019 23:29:39 -0800

It could be just coding error, could you show the control stream?

> On Feb 3, 2019, at 12:44 PM, Singla, Sumeet K <> wr=
> Hello everyone!
> I have a question. I was trying to build a 2-compartment PK model for mari=
juana use in occasional and chronic smokers. Initially, I was using providin=
g rate constants K12 and K21 ­in PK block and it resulted in poor fitti=
ng. Then, I later changed to CL,V1, V2 , Q and it resulted in proper fitting=
. I was perplexed as to why I couldn’t get a proper fit by providing=
 rate constants? I tried to look online but couldn’t find any proper=
 explanation about when (or not) we should use micro constants in PK block t=
o define our model in NONMEM? Does anyone has any useful insights into this?=

> Regards,
> Sumeet Singla
> Graduate Student
> Dpt. of Pharmaceutics & Translational Therapeutics
> College of Pharmacy- University of Iowa

Received on Mon Feb 04 2019 - 02:29:39 EST

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