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Painkillers Less Effective for Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) affects up to 10% of the community. There are different forms of IBS but all of them involve unexplained gut pain. Researchers at The University of Adelaide have now worked out why after discovering that the immune system is defective in people with IBS.

The research, which explains why some painkillers don’t offer satisfactory pain relief, has been published in Brain, Behavior and Immunity. “This study is the first to give us a real understanding of the interaction between the immune system and pain symptoms in IBS patients,” says lead author Dr Patrick Hughes.

“The gut contains specialised immune cells, known as monocytes and macrophages. Our research has shown that in healthy people, these immune cells normally secrete opioid chemicals, like morphine, that block pain. But in people with IBS, the opioid production by these cells is defective,” he says.

“So it’s no wonder that people with IBS are experiencing ongoing periods of unexplained pain. And if the immune system is defective, it may also mean that painkilling medications taken by the patient to relieve their symptoms are not being adequately converted to pain relief.”

Hughes says the exact cause of pain in IBS sufferers remains unknown, “but we have now confirmed, and detailed, information about the important role of the immune system in this pain response.

“It’s our hope that this work could eventually lead to more targeted treatments for IBS sufferers to help treat or prevent the long-term pain they experience,” Hughes says.