Tissue storage of drugs

TISSUE STORAGE OF DRUGS

Some drugs accumulate in specific tissues

Examples are

  • Heart - Digoxin
  • Liver - Chloroquine, digoxin, cadmium
  • Kidney -  digoxin, chloroquine, cadmium
  • Iris - atropine
  • Bone and teeth  - tetracycline
  • Adipose tissue - thiopentone, ether, DDT
  • storage in fat long due to poor blood supply
  • Mercury - RBC
  • Arsenic = Nail and hair

These specific storage sites are to be borne in mind when these drugs are administered or in treating their toxicities

Redistribution

  • Occurs in highly fat soluble drugs- Initially taken up by brain, heart, kidney
  • Later deposited in less vascular tissues – muscle, fat
  • On redistribution, plasma concentration falls leading to loss of drug action
  • On repeated doses, these sites fill up leading to longer action of the drug.
Last modified: Wednesday, 25 April 2012, 5:50 AM