What is the process called when a person needs larger and larger doses of a drug to feel its effect?

The process in which a person requires larger and larger doses of a drug to achieve the same effect is known as tolerance. Tolerance occurs because the body adapts to the presence of the drug, leading to a diminished response over time. As the individual's brain and body become accustomed to the drug, they may need to increase the dosage to regain the initial effects they experienced.

This physiological adaptation can result from various factors, including metabolic changes that enhance the clearance of the drug from the body or neurochemical adjustments that occur in response to the drug's presence. Tolerance is an important concept in the study of substance use and can contribute to patterns of increased consumption and potential dependency.

While withdrawal, dependency, and addiction are related concepts in the context of drug use, they do not specifically address the increasing dosage required to achieve effects, which is the hallmark of tolerance.