**3.2 Assessment of overdose risk and use of naloxone**

It is prudent to consider any patient using prescription drugs with the potential to cause overdose to be at some risk of such an outcome, even when that risk is relatively low. For patients considered to be at greater than low risk, proactive prescription of naloxone to mitigate the risk of overdose is the current standard of care and is endorsed by the AMA, CDC, and many other influential public health organizations [37].

To better assess overdose risk, Zedler and colleagues developed a new tool first presented in 2015, called the Risk Index for Overdose or Severe Opioid-induced Respiratory Depression, or RIOSORD, which has been validated in a veteran population of almost two million patients. It contains 17 questions, with a maximum score of 115. Included in the assessment are questions regarding history of psychiatric disorder, presence of pulmonary or liver disease, use of an extended-release opioid,

concurrent use of a benzodiazepine or antidepressant, daily morphine equivalent dose (MED), and any recent hospitalizations or emergency department visits [38].

Naloxone is an opioid receptor antagonist and will reverse the respiratory depressant effect of opioids [9]. There are multiple formulations of naloxone which vary by route of administration (intranasal, intramuscular, or intravenous), cost, and shelf life. All are highly effective, and many states offer access to naloxone without a prescription.

As previously noted, screening tools are imperfect and will fail to identify some individuals who will develop aberrant drug-related behaviors. These tools are not a substitute for common sense and good clinical judgment over time. However, they do contribute to the enhancement of patient safety, patient-provider trust, and risk mitigation for patients prescribed or being considered for opioid therapy for treatment of chronic pain.
