Opioids and chronic pain Opioids are a class of medicines taken to help reduce pain. They work on the central nervous system to slow down nerve signals between the brain and the body. This can reduce feelings of pain, but opioids may also produce unwanted effects, ranging from constipation to dangerous slowing down of a person’s breathing. This video aims to help people make an informed decision in partnership with their doctor about whether to start taking an opioid medicine for chronic (ongoing) non-cancer pain. We developed this animated video in partnership with NPS MedicineWise to provide information to people who may be considering taking opioids for chronic (ongoing) non-cancer pain.