Summary: Using opioids for chronic pain that is not from cancer has become a fight. There are almost no high-quality clinical studies on opioid use in chronic pain treatment. Some experts think such use is justified. Others think opioids add nothing. The problem is that neither view rests on clinical data. To end this debate, we need large, well-designed studies of opioids across different chronic pain conditions.
One of the hardest questions doctors face is whether to prescribe opioids for chronic pain that is not from cancer.
But experts say most views for and against opioids seem to rest on ideas and beliefs, not solid science. Some doctors strongly favor opioids. Others are against them. Yet it seems there is not enough evidence from large studies either way.
Experts say we urgently need bigger clinical studies. But any study of opioids in chronic pain would need thousands of patients. That is because chronic pain has many causes, like autoimmune disease, nerve disease, genetic disorders, and more. Studies also need to compare opioids with placebo and with other non-opioid painkillers.
The problem with today’s data is that it is just too small. So very few studies give useful answers on opioids for chronic pain. Opioid studies are also hard to run. They are often stopped early or pulled. Right now, no large study of opioids for chronic pain is underway.
If we search PubMed for “opioid and chronic pain,” there are more than 16,000 research articles. Yet very few are clinical studies. Barely one study is worth a look. It is the SPACE study done in 2018, and it studied the benefits of opioids over 12 months.
The study did not find opioids better than non-opioid treatments. But the study had serious limits. First, it focused mainly on low back pain and arthritis. In many people these conditions keep getting worse as bones weaken. The study also put tramadol in the non-opioid group. But tramadol is a man-made opioid with a strong painkilling effect.
Yet another study found that barely one-fifth of patients gained much from long-term opioid therapy in chronic pain treatment. But that study was a phone survey, and this kind of study has limits.
A strong study was also published in the Cochrane review. It found that the opioid tapentadol worked better for chronic pain than more commonly abused opioids like oxycodone. But these findings matter little in the clinic.
Put simply, there are not enough studies to answer the most basic questions. Who will do better on opioids than on other drugs like NSAIDs? If a doctor does choose opioids, which one fits which kind of chronic pain? And what role should opioids play in long-term chronic pain care?
Even studies on the safety of long-term opioid therapy for chronic pain are few. One Australian study tied long-term opioid use to risky behavior, like asking for an early refill. But it did not look at bigger problems like overdose.
What is worrying is that we may never see large clinical trials of opioids in chronic pain. Still, attitudes toward opioids have shifted a lot. Public health policies are changing fast and pushing against opioid use.
In fact, heavy opioid use during chronic pain care can lead to long-term addiction. Then a person may need dedicated opioid addiction treatment.
Of course, new papers on opioid use come out all the time. But they are reviews, meta-analyses, and look-back studies built on old findings and data. A new study built on old, poor-quality data cannot answer key questions with confidence.
Frequently asked questions
Which opioid is best for chronic pain?
No one can say yet, because the studies that would answer it have not been done. One Cochrane review found tapentadol worked better for chronic pain than more commonly abused opioids such as oxycodone. But those findings matter little in the clinic. There is still no solid evidence on which opioid, if any, fits a specific kind of chronic pain.
Do doctors still prescribe opioids for chronic pain?
Some do and some do not. The split runs on belief more than data. Some doctors strongly favor opioids for chronic pain not caused by cancer. Others strongly oppose them. Neither side has large clinical trials behind it. Meanwhile, attitudes toward opioids have shifted. Public health policies are changing fast to discourage their use.
Are opioids better than other painkillers for chronic pain?
The best trial so far says no. The 2018 SPACE study followed patients for 12 months. It did not find opioids better than non-opioid treatments. It had real limits. It mainly studied low back pain and arthritis. And its non-opioid group included tramadol, which is itself a man-made opioid. Who does better on opioids than on drugs like NSAIDs is still unanswered.
Is long-term opioid use safe for chronic pain?
The safety evidence is thin. Few studies have looked at long-term opioid therapy for chronic pain. One Australian study tied long-term use to risky behavior such as asking for early refills. But it did not look at overdose. Heavy opioid use during chronic pain care can lead to long-term addiction. That then needs dedicated opioid addiction treatment.
Dr. Gurpreet Singh Padda, MD, MBA, MHP
