RT Book, Section
A1 Shargel, Leon
A1 Wu-Pong, Susanna
A1 Yu, Andrew B.C.
SR Print(0)
ID 56603200
T1 Chapter 10. Physiologic Drug Distribution and Protein Binding
T2 Applied Biopharmaceutics & Pharmacokinetics, 6e
YR 2012
FD 2012
PB The McGraw-Hill Companies
PP New York, NY
SN 978-0-07-160393-5
LK accesspharmacy.mhmedical.com/content.aspx?aid=56603200
RD 2024/04/16
AB After  a  drug  is  absorbed  systemically  from  the  site  of  administration,  the  drug  molecules  are  distributed  throughout  the  body  by  the  systemic  circulation.  The  location,  extent,  and  degree  of  distribution  are  dependent  on  the  drug's  properties  and  individual  patient  characteristics  such  as  organ  perfusion  and  blood  flow.  The  drug  molecules  are  carried  by  the  blood  to  the  target  site  (receptor)  for  drug  action  and  to  other  (nonreceptor)  tissues  as  well,  where  side  effects  or  adverse  reactions  may  occur.  These  sites  may  be  intra-  and/or  extracellular.  Drug  molecules  are  distributed  to  eliminating  organs,  such  as  the  liver  and  kidney,  and  to  noneliminating  tissues,  such  as  the  brain,  skin,  and  muscle.  In  pregnancy,  drugs  cross  the  placenta  and  may  affect  the  developing  fetus.  Drugs  can  also  be  secreted  in  milk  via  the  mammillary  glands,  into  the  saliva  and  into  other  secretory  pathways.  A  substantial  portion  of  the  drug  may  be  bound  to  proteins  in  the  plasma  and/or  in  the  tissues.  Lipophilic  drugs  deposit  in  fat,  from  which  the  drug  may  be  slowly  released.