Final answer:
The section of the package insert that describes how a drug works is the Clinical Pharmacology section, which includes pharmacodynamics and pharmacokinetics information.
Step-by-step explanation:
The section of the package insert that describes how a drug works is Clinical Pharmacology. This section includes information on the pharmacodynamics and pharmacokinetics of the drug, such as how the drug affects the body and how the body processes the drug. Information such as absorption, distribution, metabolism, and excretion (ADME) of the drug, and how these factors influence the drug's efficacy and safety profile, can be found in this section. During the clinical development phases, pharmacokinetic evaluation plays a key role in determining a drug's potential for success in the marketplace by assessing parameters like bioavailability and half-life. Pharmacokinetic principles and analyses are crucial throughout the drug discovery and development process, influencing decisions on compound selection and optimization of dosage.