Absorption and Metabolism Of Xenobiotics: An Overview

Abstract

Xenobiotics are chemicals found in organisms, but not expected to be produced or present in them; or they are chemicals found in much higher concentrations than usual. There are five possible processes of intestinal absorption of Xenobiotics, they are active transport, passive diffusions, Pinocytosis, filtration through “pores” and lymphatic absorption. There are number of factors which alter the rate of Xenobiotics absorption which include diet, motility of intestine, interference with gastro intestinal flora, changes in the rate of gastric emptying, age, and the dissolution rate. Xenobiotics are metabolised by biotransformation or detoxification reactions and they are classified into phase one and phase two reactions. Phase one reactions include oxidations reaction, reduction, hydrolysis and phase two reactions include sulfation, acetylation, methylation and conjugation with glucronic acid, glutathione and glycine. Excretion of Xenobiotics occurs through urine, faeces, breath and sweat.