Opioids for Arthritis Pain: Risks and Benefits
Some arthritis patients who struggle with aching joints take prescription medications known as opioids to blunt the pain. Unfortunately, these same drugs have earned a frightening reputation in recent years.
Mounting news reports detail their widespread abuse that has led to thousands of overdose deaths in the United States each year. The Centers for Disease Control and Prevention (CDC) responded to this crisis in 2016 by encouraging physicians to curb their prescribing of these pain-relieving drugs. A growing number of doctors and hospitals now prescribe opioids sparingly, if at all.
Nonetheless, some rheumatologists still believe that opioids may be appropriate for certain arthritis patients. For example, a survey of 501 patients with rheumatoid arthritis published in 2016 in Clinical Rheumatology found that 40 percent had used opioids and that 12 percent took the drugs on a regular basis.
Before you consider trying one of these potent medicines to manage pain, it’s essential to balance the benefit you might gain against the drugs’ well-known risks.
What is an opioid?
Opioids get their name from opiates, which are compounds found in the poppy plant such as morphine and codeine. Doctors have used constituents of the plant as medicine for millennia, but morphine was first extracted and administered for pain relief in the 19th century.
The opioids used to treat pain today are produced from both natural and synthetic materials. Opioid preparations (a combination including other pain drugs) include oxycodone (OxyContin), hydrocodone and acetaminophen (Vicodin and others), hydromorphone (Dilaudid), and fentanyl. The street drug heroin is also an opioid.
When your joints ache, they send pain signals by way of the nerves to the brain. Opioids work by attaching to receptors in the brain, reducing the strength of those signals. However, opioids also act on the so-called reward region of the brain, which can produce a feeling of euphoria.
Worth the risk?
In the past, doctors primarily used opioids to treat pain in cancer patients or people with terminal illnesses. However, that began to change in the 1990s, when opioids were promoted as safe and effective for controlling chronic pain, a condition that doctors began to treat more aggressively. Sales of opioids in the United States quadrupled between 1999 and 2014.
There’s no doubt that opioids relieve acute pain, such as that caused by an injury or following surgery. But how well opioids ease the long-term, chronic pain of arthritis and other conditions is less certain.
Some arthritis patients who rely on the drugs say that the pills and patches take the edge off their joint pain. Others only use opioids sporadically, when their pain is at its worst. But how much benefit any given patient may expect to get from an opioid is questionable, based on past research.
A 2014 review of 22 clinical studies by the Cochrane Collaboration, a group of physicians that evaluates the evidence for medical therapies and procedures, found that opioids may provide a small improvement in pain for people with knee or hip osteoarthritis. The average opioid user in these studies said his or her pain level improved three points on a scale of zero (no pain) to 10 (extreme pain).
But patients in those studies who were treated with placebo pills said that their pain improved by two points, suggesting that the actual benefit an opioid offers an osteoarthritis patient is very modest.
Meanwhile, a similar review by the Cochrane Collaboration published in 2011 found modest evidence that opioids can relieve rheumatoid arthritis pain. But the authors of both Cochrane reviews worried that any benefits opioids offer patients with chronic pain may be outweighed by the risks they carry for side effects, some potentially fatal.
For starters, the gastrointestinal system is lined with opioid receptors, which may explain why the drugs can slow down peristalsis, or the movement of food through the digestive tract. As a result, many opioid users complain of constipation. Opioids can also make you drowsy and foggy-brained, which may help explain why new users increase their risk for fractured bones nearly fivefold, at least in the few weeks after they start taking the drugs, perhaps from falls.
Long-term use of an opioid can have another surprising downside: increased pain. Taking opioids is known to induce a condition called hyperalgesia, in which the nerves become increasingly sensitive, sending louder and more frequent pain signals to the brain.
Repeated use of an opioid almost always leads to tolerance, meaning you need increasingly higher doses to get the same pain relief. Similarly, some people grow to crave the feeling of euphoria that opioids can trigger, and over time it takes larger and larger doses to achieve that sensation.
Most routine users become physically dependent on the drug, which causes them to experience withdrawal symptoms such as chills, insomnia, diarrhea, and others if they stop taking it (these symptoms can be minimized through proper tapering of the dose).
Escalating doses of opioids can lead to addiction. Only a small fraction of patients treated with opioids become addicted to these pain medications. But for those who do, the compulsion to obtain and use the drugs can have catastrophic consequences. Not only can addiction destroy personal relationships and careers, but taking higher and higher doses is risky business, since opioids can impair breathing, which is a cause of death in overdoses.
Special concerns for older adults
Chronic pain is common among older adults, affecting some 40 percent of them. Yet older men and women who take opioids for pain must do so with extra caution.
As you age, changes in kidney function alter the way your body processes medicine, which could cause an opioid to accumulate and potentially lead to an overdose. Older adults often take several medications, some or all of which could interact with an opioid, especially ones in the class of drugs known as benzodiazepines, often prescribed for anxiety, insomnia, and other conditions. Age-related problems with memory—“Did I take my morning pill yet?”—could cause an individual to accidentally ingest a potentially dangerous double dose.
Despite the risks that opioids carry, the drugs may be a reasonable option for certain arthritis patients. The American College of Rheumatology recommends opioids for patients who don’t get adequate pain relief from other medications, and for those who would benefit from joint-replacement surgery, but are either unable (due to poor health) or unwilling to undergo the procedure.
If your doctor recommends an opioid, you may want to ask for a short-acting pill instead of one of the newer long-acting (extended-release) versions; the latter are commonly prescribed for chronic pain, but people who use them have an increased risk of dying from overdoses, heart attacks, and other causes, according to a 2016 study in JAMA.
It’s also worth discussing whether another type of pain medication, such as nonsteroidal anti-inflammatory drugs (NSAIDs), anticonvulsants, or certain antidepressants, may offer a safer alternative.