Why does tolerance to opioids, leading to increased dosage requirements in pain management, develop within the neural circuit?

💡 Explanation

Opioid tolerance develops because repeated opioid exposure causes receptor desensitization in the reward circuit. This reduces the receptors' signaling efficacy. Therefore, higher doses are needed to achieve the same analgesic effect, rather than changes in liver enzymes, endorphins, or permeability.

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