Final answer:
Dependence is characterized by the need for continued or repeated use of a drug to maintain a desired state, including avoiding withdrawal, and encompasses both physical and psychological dimensions. Tolerance, a need for higher drug doses for the same effect, is a component of physical dependence, while psychological dependence relates to emotional need for the drug.
Step-by-step explanation:
Dependence can be defined as the condition in which stopping the use of a drug produces physical and/or psychological symptoms. This state can include both tolerance, the need for increasingly larger doses to achieve the initial effect, and withdrawal symptoms when the drug is not used. Physical dependence involves bodily function changes that result in withdrawal symptoms upon cessation, while psychological dependence refers to an emotional need for the drug, often to relieve psychological distress.
Dependence is a condition that implies significant adaptation of the body to the presence of a drug. Tolerance is a component of dependence and is characterized by the need for greater amounts of a drug to achieve the same effects as earlier, lower doses did. This can lead individuals to consume more of the drug, risking overdose and death. In contrast, psychological dependence is about the emotional and mental preoccupation with the drug, often used to alleviate emotional pain or discomfort.