This type of categorisation of drugs is from a biological perspective and categorises them by the anatomical or functional change they induce. Drug classes that are defined by common modes of action (i.e. the functional or anatomical change they induce) include:
* Antifungals
* Antimicrobials
* Antithrombotics
* Bronchodilator
* Chronotrope (positive or negative)
* Decongestant
* Diuretic or Antidiuretic
* Inotrope (positive or negative)