Farmacologie -

describes drug absorption, distribution, metabolism, and excretion (ADME). Absorption determines how a drug enters the bloodstream (e.g., oral, intravenous, transdermal). Distribution involves the drug’s movement to tissues, influenced by blood flow, protein binding, and barriers like the blood-brain barrier. Metabolism, primarily hepatic via cytochrome P450 enzymes, converts lipophilic drugs into more hydrophilic metabolites for excretion. Excretion occurs mainly via the kidneys, but also through bile, lungs, and sweat. Pharmacokinetic models (e.g., compartmental analysis) help predict drug concentrations over time, enabling dosing regimens that maximize efficacy while minimizing toxicity.

The journey from a chemical idea to a marketed medicine is long, costly (often exceeding $1 billion and 10–15 years), and highly regulated. The process typically follows these stages: farmacologie