In the context of drug addiction, what causes escalating drug cravings despite diminished euphoric effects with repeated use?

💡 Explanation

Drug-induced dopamine release initially causes euphoria; however, repeated exposure leads to dopamine receptor downregulation combined with sensitization of the mesolimbic pathway. This increases craving because the brain adapts to expect the drug, resulting in enhanced reward-seeking behavior rather than sustained euphoria, therefore the craving intensifies.

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