What term refers to the reduced effect of a drug after repeated use, prompting a higher dosage for the same effect?

The term that refers to the reduced effect of a drug after repeated use, which leads to the need for a higher dosage to achieve the same effect, is tolerance. When an individual uses a substance regularly, their body becomes accustomed to its presence, and over time, the same dosage produces a diminished effect. This physiological adaptation can occur due to various mechanisms, including changes in receptor sensitivity or metabolism. As tolerance develops, a person may feel compelled to increase their dosage, which can lead to further dependence and potential health risks.

Cross tolerance, while related, specifically refers to the phenomenon where tolerance to one drug extends to another drug that acts on similar pathways. Reverse tolerance, also known as sensitization, occurs when smaller doses of a drug produce increased effects over time, opposite of tolerance. Behavioral tolerance involves learning and adaptation to the effects of a drug in a specific environment rather than changes in the body's pharmacological responses. These distinctions clarify why tolerance is the most appropriate term for the situation described.