Question

Cross-tolerance to a drug is defined as:

1. one drug that can prevent withdrawal symptoms from another drug.
2. an allergic reaction to a classification of drugs.
3. one drug that results in a lessened response to another drug.
4. one drug that can increase the potency of another drug.

Answer 1

Cross-tolerance refers to a reduced response to one drug due to tolerance developed to a similar drug, and is not related to withdrawal symptoms which occur when drug use is discontinued.

Step-by-step explanation:

Cross-tolerance to a drug is defined as a scenario where one drug results in a lessened response to another drug due to shared pathways or receptor actions. When an individual has developed tolerance to one substance, it may reduce the effects of a second substance if both drugs act within the same system in the body. This situation is not the same as withdrawal, which is the adverse physical or psychological reaction experienced when stopping or reducing the intake of a drug to which one has developed physical dependence. On the contrary, tolerance, both physical and psychological, often leads to the need for increasing dosages to achieve the same effect and may contribute to substance use disorders.