People taking prescribed opioids for pain relief have a higher risk of developing mood disorders such as anxiety, according to Australian researchers. Their study, published in Pain Medicine and revealed to the public on Tuesday, is based on the analysis of patients who were prescribed opioids to treat an array of physical health conditions including burns and trauma surgery. Epidemiologist Janni Leung from the National Centre for Youth Substance Use Research at the University of Queensland (UQ) said the results showed higher doses of prescription opioids could increase the risk of “developing depressive, bipolar and anxiety disorders, particularly with prolonged use.” “There has been a lot of research around addiction to opioids — commonly used in cancer treatment or acute pain — but there is limited understanding about how they affect the development of mood disorders,” Leung said, adding that the “relationship between chronic pain and mental health is complex, as each condition contributes to the other.” The paper’s co-author, Daniel Stjepanovic from the same centre in UQ, said the findings indicated why it was vital to understand all the risks before prescribing medication to a patient. “The effects on mental health should be taken into account when prescribing opioids, especially in individuals who are at risk of mood disorders such as anxiety or depression,” Stjepanovic said. Noting that the use of prescription opioids had increased substantially over the past two decades, the report’s authors said it was “incredibly important” to understand the role such drugs, which can potentially be addictive, “play in the development of these mood disorders.” They said that research into the influence of opioids on mental health was still in the early stages, and further studies were needed to better comprehend how such medications can influence mood disorders.