Final answer:
An adverse effect is a harmful and undesired effect of a medication; a contraindication is a scenario where a drug should not be used, and expected side effects are known potential reactions to a drug during normal use.
Step-by-step explanation:
An adverse effect is an undesired harmful effect resulting from a medication or other intervention such as surgery. A contraindication is a specific situation in which a drug, procedure, or surgery should not be used because it may be harmful to the person. The term expected side likely stands for expected side effects, which are known, potential reactions to a medication that may occur in the anticipated therapeutic use.
These concepts are essential in the fields of pharmacokinetics and pharmacodynamics during the drug discovery and development process. Pharmacokinetics involves how the body affects a specific pharmaceutical compound, including the phases of absorption, distribution, metabolism, and excretion (ADME). Whereas pharmacodynamics examines the biological effects of drugs and their mechanisms of action within the body.