Book excerpt: Pharmacological knowledge among medical students can have a very short 'half life': students often fail not because they have failed to study, but because they have been unable to retain key knowledge and reproduce it in an exam setting. This book takes an alternative route to the conventional approach of comprehensively exploring each individual drug and its features: not only can such an approach overwhelm and make knowledge retention difficult, but the current exam format makes questions structured in this way unlikely anyway. Instead of aiming to be completely comprehensive, it examines drugs systematically by classifications, mechanisms of action, therapeutic uses and side effects, enabling students to gain the distilled, functional grasp of pharmacology that their exams actually demand quickly and clearly.