The opioid painkiller tramadol has only a limited effect on chronic pain and likely increases the risk of serious adverse events, including cardiac complications, according to a new systematic review.
The Danish researchers concluded that the potential harms of tramadol ‘likely outweigh its limited benefits’ and recommended minimising its use for chronic pain management.
Published in the BMJ Evidence-Based Medicine, the systematic review with meta-analysis and trial sequential analysis included 19 randomised controlled trials involving more than 6,500 adults with various types of chronic pain. These included neuropathic pain, osteoarthritis, chronic low back pain and fibromyalgia, with treatment durations ranging from two to 16 weeks.
While pooled data showed tramadol did reduce pain levels, the effect size was small and fell below the threshold typically considered clinically meaningful.
Eight of the trials reported serious adverse events during follow-up, and patients receiving tramadol were twice as likely to experience serious harm as those given placebo. Cardiac events such as chest pain, coronary artery disease and heart failure accounted for the majority of these.
Use of tramadol was also associated with an increased risk of milder side effects such as nausea, dizziness, constipation and sleepiness.
In addition, a possible link with cancer was identified, though the researchers cautioned that short follow-up periods made this finding uncertain.
Concerns over opioid safety
Although the researchers acknowledged a high risk of bias across the included studies – potentially leading to overestimated benefits and underestimated risks – they said the findings aligned with broader concerns about opioid safety.
‘Tramadol may have a slight effect on reducing chronic pain (low certainty of evidence) while likely increasing the risk of both serious (moderate certainty of evidence) and non-serious adverse events (very low certainty of evidence),’ they concluded.
The researchers called for healthcare providers to reduce the use of tramadol and other opioids where possible, noting that around 60 million people globally experience opioid addiction, and that opioid-related deaths continue to rise.
Previous research has shown that one in three patients with rheumatic and musculoskeletal conditions are at risk from long-term opioid use.
A version of this article was originally published by our sister publication The Pharmacist.
