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Opioids are potent, addictive analgesics that trick and trap us by creating the fleeting euphoria of analgesia (pain-free), but the sustained sickness of hyperalgesia (pain-sensitivity). The euphoria of analgesia and the sickness of hyperalgesia are polar opposites that reinforce each other: the euphoria blinds us to the sickness, and the sickness makes us crave the euphoria. Perversely but predictably, opioids create, aggravate, and perpetuate the very sickness of hyperalgesia that they falsely seem to cure, thus placing many potent analgesics in a bad light.