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PK data from individuals who vomited after drug ingestion

From: Seng Kok Yong <skokyong>
Date: Thu, 27 Aug 2009 11:09:03 +0800

Dear NM-users,


I have a question regarding NONMEM modeling of PK data from individuals
who vomited after drug ingestion. Basically, I have a set of data from
about 150 subjects (about 5 measurements per subject) who orally
ingested alcohol at time = 0 h. However, about 15% of this group
vomited more than 1 h post-dose. Based on NONMEM modeling of PK data
from subjects who did not vomit during the study, the mean elimination
half-life is about 30 min.


May I ask if I should model vomiting incidence (a "yes" or a "no") as a
categorical covariate for analysis of all the data? I have demographic
covariate information at hand. Or, should I introduce a mixture model
during NONMEM modeling? I would expect the vomiting subgroup to display
different values for Vd, Ka etc as compared to the non-vomiting


Thank you very much for your time and kind advice.


Best wishes,

Kok-Yong Seng, PhD

DSO National Laboratories

Republic of Singapore


Received on Wed Aug 26 2009 - 23:09:03 EDT

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