Friday, December 1, 2017

Tramadol: A Case of Misclassification?


Although tramadol was being considered for classification as a controlled drug back in 2007, it remained an uncontrolled drug.1 A decade later, Health Canada is reconsidering the decision and may re-categorize tramadol as an opioid.1

Tramadol is a painkiller that increases serotonin levels in the body like antidepressants do, leading to some analgesia.1 In addition, CYP2D6 in the liver then converts tramadol to a compound called M1, which is an opioid that provides pain relief similarly to morphine.1 One thing to remember is the pharmacogenomics involved with the conversion of tramadol to M1.1 Some individuals have weak CYP2D6 activity and do not receive the opioid effect, whereas, others may have rapid conversion and acquire a large opioid effect.1

The classification of Tramadol as an opioid is being contemplated due to multiple health care professionals voicing concerns as well as a report on opioid trends from the Canadian Institute for Health Information (CIHI) released last week.2 According to the report, tramadol prescriptions have increased 30% and daily doses have increased by 23% between 2012 and 2016.3 Despite the Canadian non-opioid classification, CIHI included tramadol in their report on opioids because the World Health Organization classifies it as an opioid, as does the United States’ Drug Enforcement Administration and the manufacturers' scientific description.2

Tramadol has the potential to be abused, misused, and can cause dependence especially at higher doses.2,4 Its classification as a non-opioid makes for minimal reporting requirements resulting in a lack of data to help us measure the extent of its abuse and misuse in Canada.2

The opioid crisis does not look like it will resolve any time soon as there is no simple solution for the problem. Therefore, making even the smallest of changes, such as modifying the classification of tramadol to an opioid and the resulting alterations in reporting requirements, could prove crucial.

Now we wait and see if Health Canada will make this change.

References:
1. Juurlink, D. (2017, November 27). Why Health Canada must reclassify tramadol as an opioid. The Globe and Mail. Retrieved from https://www.theglobeandmail.com/opinion/why-health-canada-must-reclassify-tramadol-as-an-opioid/article37089174/

2. Howlett, K. (2017, November 22). Health Canada eyes opioid restrictions for popular painkiller. The Globe and Mail. Retrieved from https://www.theglobeandmail.com/news/national/health-canada-eyes-opioid-restrictions-for-popular-painkillertramadol/article37048483/

3. Canadian Institute for Health Information. (2017). Pan-Canadian Trends in the Prescribing of Opioids. Ontario: Canadian Institute for Health Information. Retrieved from https://www.cihi.ca/sites/default/files/document/pan-canadian-trends-opioid-prescribing-2017-en-web.pdf




4Purdue Pharma. (2016). PRODUCT MONOGRAPH INCLUDING PATIENT MEDICATION INFORMATION : Zytram XL®. Pickering. Retrieved from http://purdue.ca/wp-content/uploads/2015/12/Zytram-XL-PM-EN.pdf?4eb3c6