## **Core Concept**
Naltrexone is an opioid receptor antagonist used in the management of opioid dependence and alcohol dependence. It works by blocking the opioid receptors in the brain, thereby preventing the euphoric effects of opioids. This mechanism is crucial for its therapeutic application.

## **Why the Correct Answer is Right**
The correct answer, , indicates that naltrexone is used to manage opioid dependence. Naltrexone achieves this by competitively inhibiting the opioid receptors, specifically the mu (μ), kappa (κ), and delta (δ) opioid receptors. By blocking these receptors, naltrexone prevents the action of opioids, thereby reducing the craving for opioids and preventing relapse in individuals who have been detoxified. This action is beneficial in maintaining sobriety in opioid-dependent patients.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is incorrect because, although naltrexone might indirectly affect withdrawal symptoms by blocking opioid receptors, its primary use is not to manage acute withdrawal symptoms but to maintain sobriety.
- **Option B:** This option is incorrect because naltrexone does not act as an agonist; it acts as an antagonist, blocking opioid receptors.
- **Option C:** This option might seem plausible but is incorrect in the context of how naltrexone is primarily used; it's not specifically for managing overdose but for long-term management of opioid dependence.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that naltrexone is most effective when used in conjunction with counseling and social support. It's also worth noting that before starting naltrexone, patients should be opioid-free for a certain period (usually 7-10 days) to prevent precipitating withdrawal.

## **Correct Answer:** . Manage opioid dependence.