Final answer:
The term related to the amount of drug administered to produce a therapeutic effect is pharmacotherapeutics. It ensures the correct dosage to treat and prevent diseases while minimizing the risk of side effects.
Step-by-step explanation:
The term related to the amount of drug administered to produce a therapeutic effect is D. pharmacotherapeutics. This branch of medicine deals with the use of drugs and the method of their administration for the purpose of treating and preventing disease. Posology is the study of drug dosages, while pharmacodynamics involves the effects of drugs on the body. Toxicology investigates the adverse effects of chemicals on living organisms, and pharmacy is the science and practice of preparing and dispensing drugs.
When determining the dosage of a drug, it is important to consider factors such as the patient's age, body mass, liver and kidney function, and potential food effects on pharmacokinetics. These considerations ensure that therapeutic drug levels are achieved without significant toxicity. Moreover, pharmacokinetic studies are essential from drug discovery to clinical development for evaluating drug exposure, metabolism, and plasma drug levels associated with toxicity to define the no observed adverse effect level for human clinical trials.