how the drug gets into the body, and then into cells:
enteral (GI): oral, sublingual, rectal
parentral (non-GI): inhalation, IV, SQ, IM, topical, transdermal
depends on gastric motility, surface area available, solubility of the drug, drug-drug interactions, pH, hepatic blood blow, drug particle size, drug formulation
A theoretical concept to understand where the drug goes once its absorbed, the drug is said to distribute in an imaginary volume. example: in fat tissues, plasma, other interstitial areas, difficult to actually calculate, therefore use an "average"
Different for each drug, considers solubility, lipophillic vs. hydrophilic
Different for each person, size, adipose tissue, body water content