What is the best description of drug tolerance?

Drug tolerance refers to a person's diminished response to a drug following its repeated use. As an individual continues to consume a substance, their body adapts to its effects, leading to a situation where the individual requires higher doses to achieve the same level of intoxication or effect that was initially experienced. This phenomenon is characterized by decreased sensitivity to the effects of the drug over time, which is reflected in the correct choice.

Consequently, individuals who have developed tolerance may find that the initial amount of the drug does not produce the same level of intoxication, necessitating increased intake for the desired effect. This concept is crucial for understanding substance use and potential substance use disorders, as it can lead to escalating consumption and associated risks such as dependence and overdose.