Why taking morphine, oxycodone can sometimes make pain worse
By Kelly Servick
May. 30, 2016
There’s an unfortunate irony for people who rely on morphine, oxycodone, and other opioid painkillers: The drug that’s supposed to offer you relief can actually make you more sensitive to pain over time. That effect, known as hyperalgesia, could render these medications gradually less effective for chronic pain, leading people to rely on higher and higher doses. A new study in rats—the first to look at the interaction between opioids and nerve injury for months after the pain-killing treatment was stopped—paints an especially grim picture. An opioid sets off a chain of immune signals in the spinal cord that amplifies pain rather than dulling it, even after the drug leaves the body, the researchers found. Yet drugs already under development might be able to reverse the effect.
More: http://www.sciencemag.org/news/2016/05/ ... pain-worse