A 56-year-old with painful diabetic neuropathy needs an opioid that can treat both nociceptive and neuropathic pain. Which drug is appropriate?

Tapentadol is the appropriate choice for treating both nociceptive and neuropathic pain. This medication combines two mechanisms of action: it is a mu-opioid receptor agonist, which helps alleviate nociceptive pain, and it also inhibits the reuptake of norepinephrine, making it effective for neuropathic pain as well. This dual action is particularly valuable in managing painful diabetic neuropathy, a condition characterized by both types of pain.

The other options do not offer the same effectiveness for neuropathic pain. For instance, meperidine primarily acts as an opioid for nociceptive pain but lacks efficacy in treating neuropathic pain, and its use is often limited due to side effects and the potential for neurotoxicity with prolonged use. Oxymorphone and morphine are both strong opioids that are effective for nociceptive pain; however, they do not address the neuropathic component, making them less suitable for this patient's complex pain profile. Thus, the combination of opioid activity and norepinephrine reuptake inhibition in tapentadol provides a comprehensive approach for managing the patient’s painful condition.