Why does chronic opioid use increase the risk of relapse after detoxification, related to the brain's reward circuitry?

💡 Explanation

Chronic opioid use leads to neural adaptations, including sensitization of the nucleus accumbens in the reward circuit because repeated exposure alters neuronal excitability. Therefore, even after detoxification, the brain's heightened sensitivity increases craving and relapse vulnerability, rather than receptor changes.

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