Describe the concept of tolerance.

Tolerance refers to a physiological adaptation that occurs when an individual’s body becomes accustomed to a substance after repeated consumption. As a result, the individual requires increasing amounts of the substance to achieve the same effects that were previously experienced at lower doses. This phenomenon is often seen in various substances, including alcohol, opioids, and stimulants, and it can lead to escalating use as the person tries to reach the desired effects, which can exacerbate issues related to substance use disorders.

Understanding tolerance is crucial because it illustrates how the body adjusts to the presence of a substance and highlights the risk of dependency and potential overdose. Tolerance also plays a role in treatment and recovery, as those who have developed tolerance may experience withdrawal symptoms when they stop using the substance.

The other options do not accurately capture the essence of tolerance. A describes a scenario where the individual feels no effects from a substance, which is more akin to a state of desensitization rather than tolerance per se. C references cravings or psychological dependence, which relates more to the desire to use a substance rather than the body's physical adaptation to it. D mentions a temporary increase in sensitivity, which contradicts the nature of tolerance, as tolerance actually involves a reduction in sensitivity to a substance over time.