Which drug abuse craving is naltrexone primarily used to treat?

Naltrexone is primarily used to treat cravings associated with opioid abuse. It functions as an opioid antagonist, meaning it blocks the effects of opioids in the brain. This feature is particularly beneficial for individuals who are trying to recover from opioid dependency since it helps mitigate cravings and reduces the risk of relapse by preventing opioids from producing their euphoric effects.

While naltrexone has also been studied for use in treating alcohol dependence, its primary and most well-documented application remains in the context of opioid addiction. It is less effective for other substances like stimulants or nicotine, as these drugs have different mechanisms of action and cravings that naltrexone does not target effectively. Therefore, understanding the specific action of naltrexone provides insight into its role in opioid treatment and reinforces why it is the correct answer in this context.