The Risk of Chronic Opioid Utilization with Tramadol: A Narrative Review of the Literature.

Tramadol is a prescription opioid analgesic which was first approved in the U.S. in 1995. Tramadol was not a controlled substance on the federal level until August 2014 when it was classified as a Schedule-IV controlled substance. Even with it becoming a controlled substance, its utilization increased in the following years and is the second most prescribed opioid in the U.S. behind hydrocodone products. Recent research highlights tramadol's potential for psychological or physical dependence. Therefore, the objective of this article was to review all studies assessing the impact of tramadol on chronic opioid utilization and/or opioid misuse compared to other therapies. Ten published studies showed tramadol had comparable or higher risk of chronic opioid utilization and/or opioid misuse compared to other opioids, while six studies showed tramadol had a significantly lower risk. This article intends to review these findings, providing rationale and potential policy implications. While there may be some residual confounding, confounding by indication, or unmeasured biases contributing to the results seen showing higher risks, it is still concerning given the number of studies that demonstrated these findings.