absorbed in the intestine by simple diffusion
Factors affecting gastrointestinal absorption
Water intake,whether on an empty stomach,gastrointestinal motility,pH in the gastrointestinal tract and so on
Acids and enzymes secreted by the gastrointestinal tract and biochemical effects of intestinal flora
Drugs circulates through the body
Absorption through the lungs
To produce local effect on skin,eyes,nose,throat and vagina
Rectal administration
Produce a local anti-inflammatory effect
To some extent,first pass elimination can be avoided
Sublingual administration can largely avoid first pass elimination
