New Research Highlights Opioids with Highest Risk of Causing Constipation

A new study reveals which opioids are most likely to cause severe constipation, highlighting the importance of personalized pain management and dosing strategies.

2 min read

A recent study conducted by epidemiologists at the University of Manchester has shed light on the varying risks of severe constipation associated with different opioid painkillers used for non-cancer pain management. Published in BMC Medicine, the research analyzed electronic health records of over 80,000 patients in Northwest England from 2009 to 2020 to determine which opioids are most likely to lead to this common but troublesome side effect.

The study found that opioids such as morphine, oxycodone, fentanyl, and combination opioids are linked with a significantly higher likelihood of causing severe constipation compared to codeine, which showed the lowest risk among opioids evaluated. Patients taking more than 50 morphine milligram equivalents (MME) daily—roughly equivalent to 50mg of morphine or 33mg of oxycodone—were at the greatest risk for severe constipation. While the UK Faculty of Pain Medicine recommends caution at doses exceeding 120 MME per day, this threshold is currently under review.

The research utilized hospital records to identify opioid exposure and defined severe constipation as requiring interventions like enema or suppositories. These findings highlight the importance of healthcare professionals considering the relative risks of different opioids and doses when prescribing in order to improve patient outcomes.

Dr. Meghna Jani, the study's senior author, emphasized that opioid-induced constipation significantly affects quality of life, leading to longer hospital stays and increased healthcare costs. The underreporting of constipation in health records may underestimate its true prevalence, as patients often hesitate to discuss bowel issues or doctors may not always code these events.

This study aims to enable more informed, personalized pain management strategies, encouraging prescribers to consider lower doses and selecting opioids with a lower propensity to cause constipation. Ultimately, the goal is to minimize side effects and enhance patients' quality of life by making smarter, safer pain relief choices.

Source: Medical Xpress