Use of opioids for chronic non-cancer related pain, however, is more complex and controversial now that the “Decade of Pain” has come to a close. Recent evidence has demonstrated that longer durations of treatment and higher doses of opioids are associated with increased rates of falls, fractures, motor vehicle accidents, physical and psychological dependence, medication overdose and death. On top of those risks, opioids come with a variety of side effects that some patients find intolerable
Opioids can cause several side effects involving the central nervous system, including drowsiness, dizziness, mental cloudiness and nausea. There’s also the risk of developing slow, shallow breathing that can lead to severe respiratory depression and possibly damage the heart or brain; this has the potential to cause death.
Opioids also have an effect on the gastrointestinal (GI) tract because of the way they relieve pain. Opioids block receptors all over the body from sending pain signals to the brain; however, blocking these receptors in the gut impairs the function of the entire GI tract. While constipation is perhaps the most common GI complaint related to opioid use, other side effects include bloating, abdominal discomfort, gastroesophageal reflux, loss of appetite, nausea and vomiting. The GI effects of opioids may at times be so severe that patients prefer to stop the medication rather than suffer from the consequences.