Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
1990-10-4
pubmed:abstractText
We show that for drugs metabolized by one enzyme the slope of a plot of serum concentration (C) versus 1/clearance (CL) is linear with a value of 1/Vmax in the presence of substrate saturation and may be linear (rarely) or curved (usually) with a slope always greater than 1/Vmax in the presence of substrate saturation and product inhibition (competitive, noncompetitive, or uncompetitive) when the serum concentration of product varies with the serum concentration of substrate. Serum concentration, CL, and Vmax were determined for a group of six subjects receiving phenytoin monotherapy using three approaches. With each approach: 1) a plot C versus 1/CL was linear (r greater than or equal to 0.738, P less than .01); 2) the slope of this regression line did not differ significantly (P greater than .30) from 1/Vmax. We conclude: 1) our method is a simple and useful method for determination of mechanism of a drug's nonlinear pharmacokinetics (substrate saturation versus substrate saturation and product inhibition), 2) phenytoin has nonlinear pharmacokinetics due to substrate saturation only in man.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0091-2700
pubmed:author
pubmed:issnType
Print
pubmed:volume
30
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
578-84
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
New pharmacokinetic methods. II: Determination of the presence or absence of product inhibition in drugs with nonlinear pharmacokinetics.
pubmed:affiliation
Department of Neurology, Boston University School of Medicine, MA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.