PharmPK Discussion - Clearance Question

PharmPK Discussion List Archive Index page
• On 15 Jun 2006 at 07:36:26, Kate Roupe (karoupe.aaa.yahoo.com) sent the message
`Dear All,I am looking for the appropriate equation to calculate clearance. Thesubjects are to be administered a bolus IV dose (8 mg/kg or 16 mg/kg)followed by a continuous infusion (47.5 mg/kg/12 hr or 32 mg/kg/12).Thanks,Kathryn Roupe, Ph.D.Senior Pharmacokineticist`
Back to the Top

• On 16 Jun 2006 at 07:11:30, "ogwal sidney" (sidneyogwal.-a-.hotmail.com) sent the message
`The following message was posted to: PharmPKs.o.oCheck in a first course in Pharmacpkinetics and Biopharmaceutics byProff. David Bourne[Thanks Sidney, that would be http://www.boomer.org/c/p4/ or http://www.boomer.org/c/p3/Actually it's a little more complicated. Do you start the infusion atthe same time as the bolus is given? Is there a delay? After just abolus dose, clearance can be calculated as Dose/AUC (http://www.boomer.org/c/p4/c04/c0410.html). During an infusion at steadystate, clearance can be calculated as Infusion Rate/Cp(ss) (http://www.boomer.org/c/p4/c06/c0602.html). If your objective is to dose tosteady state using a bolus/infusion regimen then the second equationmay be suitable once you have verified that steady state has beenachieved (http://www.boomer.org/c/p4/c06/c0604.html). Otherwise, ifyou have enough suitable data points modeling the data in terms of Vand CL should work - db]`
Back to the Top

• On 16 Jun 2006 at 18:33:52, "Shawn D. Spencer" (shawn.spencer.-a-.famu.edu) sent the message
`Kate,Your question is suprisingly odd... almost as if part of yourquestion is missing.  Does this drug undergo (or is expected toundergo) nonlinear disposition processes, which is why you mentionedthe dose regimen?  One assumes you have limited data (i.e. no ivbolus regimens), and if so, you need only your concentration atsteady state to arrive at a clinical estimate for clearance.  It isnot likely you have clinical data without a rough estimate of yourhalf-life, and so wait at least 5 half-lives use the concentration toarrive at a preliminary estimate of clearance.  Again, one assumesthere is more to the question.Keep in touch..-Shawn`
Back to the Top

Want to post a follow-up message on this topic? If this link does not work with your browser send a follow-up message to PharmPK@boomer.org with "Clearance Question" as the subject

Copyright 1995-2010 David W. A. Bourne (david@boomer.org)