Opioid medications are highly effective against many types of pain, but not neuropathic pain, which arises from damaged or diseased nerves. Research from the National Institute on Drug Abuse suggests a way to remedy that shortcoming.
Structural alterations to an opioid compound improved analgesia in an animal model of neuropathic pain.
Researchers created hybrid compounds that combine an opioid with a molecule that prevents substance P, a neurochemical that contributes to inflammation and pain responses, from activating its receptors on nerve cells. The hybrid compounds reduced pain responses in animal models of neuropathy as effectively as parent opioids reduced animals’ responses in models of non-neuropathic pain. The findings are consistent with a hypothesis that over-activity of substance P is a source of neuropathic pain.