A recent study has warned that some opioid painkillers may carry greater risks than others, after researchers from the University of Manchester identified the drugs most strongly associated with respiratory depression and fatal overdoses.
Respiratory depression occurs when breathing becomes slow or shallow, leading to low oxygen levels in the body and high levels of carbon dioxide in the blood, and is one of the leading causes of death in cases of opioid overdose.
Opioids are among the strongest painkillers and are used to treat severe pain resulting from surgery, injuries, and cancer patients. These drugs include fentanyl, morphine, codeine, and tramadol, but they can affect areas of the brain responsible for controlling breathing.
A study involving more than 32,000 patients
In the study, published in the journal BMC Medicine, researchers analyzed the electronic health records of 32,909 adult patients in hospitals in northwest England, with the aim of identifying which types of opioids were most associated with life-threatening complications.
The researchers reviewed several medical indicators, including respiratory rate and blood oxygen levels, as well as the patients' need for the drug "naloxone," which is used to reverse the effects of opioid overdoses.
The results showed that patients who took fentanyl were three times more likely to develop respiratory problems compared to those who used codeine.
The risk of respiratory depression was also 85% higher among fentanyl users compared to morphine users.
The researchers found that using more than one type of opioid at the same time triples the risk of serious complications, and that the use of oxycodone and morphine was associated with a higher likelihood of breathing problems compared to codeine.
People taking a combination of opioids were about 50% more at risk than those using morphine alone
The researchers explained that the danger of "fentanyl" is due to its high potency and the speed at which it reaches the brain, which may lead to a sudden slowing of breathing.
The study also showed that people with chronic obstructive pulmonary disease may be the most at-risk group, as their use of fentanyl was associated with a nearly four times greater risk of breathing problems compared to codeine.
Dr. Meghna Jani, Senior Clinical Lecturer at the University of Manchester and lead author of the study, said: "Opioids are still important drugs for treating acute and severe pain, but our results show that the level of risk varies depending on the type of opioid and the dose used."
The study indicated that high doses are associated with increased risks, and even moderate doses ranging from 31 to 60 morphine equivalents per day were associated with a higher likelihood of complications.
