Pharmacotherapy options for noncancer pain: an efficacy review

http://www.clinicaladvisor.com/pain-management-information-center/treating-noncancer-pain-with-acetaminophen-nsaids-instead-of-opioids/article/487282/

Strong opioids are no more effective than acetaminophen or nonsteroidal anti-inflammatory drugs (NSAIDs) in patients with musculoskeletal disease and other forms of noncancer pain, according to a review published in Joint Bone Spine.1

Strong opioids, including morphine, fentanyl, and oxycodone, have been on the top step (step III) of the World Health Organization (WHO) analgesic ladder for many years. However, it may be time to rethink this model; when it comes to noncancer pain, strong opioids are neither strong nor effective.

“This is a review, so there is nothing here [that] we don’t already know — in fact, there is not much evidence for use of any opioids for longer than 3 months,” Troy Buck, MD, an assistant professor of anesthesiology and pain management from Loyola University Medical Center in Maywood, Illinois, told Clinical Pain Advisor.

Jahangir Maleki, MD, a pain management specialist at the Cleveland Clinic’s Center for Neuro-Restoration, agrees that opioids may be overestimated for pain. However, they have other important benefits, he notes.

“In terms of other good indications, there are many. I would invite the authors of this review to join an anesthesiologist for a day. They would see what opiates are capable of delivering before, during, and after any surgery. Opiates [achieve] more than just analgesia. Sedation, relaxation, and mood elation are great benefits, if used properly in acute conditions,” Dr Maleki told Clinical Pain Advisor.
What the Research Shows

The review authors note that there is a “stunning” lack of high-quality studies on the efficacy of step III analgesics, especially given their widespread use and abuse. Among their findings:1

Several randomized, double-blind, emergency-room trials found that IV acetaminophen was similarly effective or superior to IV morphine in patients with conditions such as renal colic, low back pain, and acute limb pain.
In a trial of 137 patients with intense and acute limb pain, there was no difference in pain relief between 1 gram of IV acetaminophen and 0.1 mg/kg of IV morphine.
In 31 studies of chronic neuropathic pain, opioids were only slightly more effective than placebo.
A meta-analysis of oxycodone used to treat diabetic neuropathy, postherpetic neuralgia, or fibromyalgia concluded there was no proof of efficacy, but there were more side effects.
A systematic review of opioids for osteoarthritis pain found them no more or less effective than NSAIDs.

All of these studies examined opioid doses below 100 mg/day morphine-equivalents. Although higher opioid doses may achieve greater analgesia, are they worth the cost?

“Getting into higher doses for any condition brings into play issues of tolerance, dependence, respiratory depression, and at very high doses, hyperalgesia,” Dr Buck pointed out.

The authors note that pain specialists in the United States have issued a petition supporting restrictions to strong opioid use in noncancer pain, limiting doses to less than 100 mg/day morphine-equivalents, for a maximum of 100 days. The action reflects the sobering statistic that opioids contribute to more than 10 000 deaths in the United States each year.1

“The fact is that opiates are great drugs if they are used properly for acute pain, but they fail miserably when we use them as a Band-Aid. We need to realize that most of the world’s opiates are sold here in the US. If opiates were truly the painkillers we thought, we would have eliminated pain from every corner. Not only haven’t we eliminated pain, [but] the opiate epidemic has directly resulted in [an] ever-growing number of drug overdoses,” said Dr Maleki.

What About Cancer Pain?

Although the mean dose of morphine for cancer pain ranges from 100 to 250 mg/day, doses exceeding 1000 mg are not unusual and have been studied in a few placebo-controlled trials. Results tend to show a good initial analgesic effect, especially for fentanyl, followed by decreasing efficacy and increasing toxicity over time. A Cochrane review of 62 trials involving more than 4000 patients found that adequate analgesia was only achieved in 29% of studies.1

The “war on pain” that was started 20 years ago has relied heavily on opioids. Is it time to say that opioids have lost the war on pain?

“I would not go that far,” said Dr Buck. “Opioids are still well indicated for acute and severe pain, such as in the post-op setting — but they are rarely indicated for chronic pain.”
Future Prospects and Key Takeaways

The development of new analgesics and new nonpharmacological approaches may be our best hope for future pain management, the authors write.

“There is no game changer on the horizon as far as new analgesics. I think [that] the future of pain management may lie more in nonpharmacological treatments, like spinal cord stimulation, peripheral nerve stimulation for neuropathic pain, and cognitive behavioral therapy interventions,” Dr Buck said.

“Primary care providers should be aware that the bulk of opioid prescriptions are distributed by general practitioners,” Dr Maleki said, noting that these clinicians are the first to field the acute onset of chronic pain.

“Primary care providers play a crucial role in preventing transition of acute pain into chronic pain. Patient education, lifestyle changes, proper diet, stress reduction, and adequate exercise, along with use of non-opioid medications are the primary management tools,” Dr Maleki concluded.
Reference

Berthelot JM, Darrieutort-Lafitte C, Le Goff B, Maugars Y. Strong opioids for noncancer pain due to musculoskeletal diseases: Not more effective than acetaminophen or NSAIDs. Joint Bone Spine. 2015 Dec;82(6):397-401. doi: 10.1016/j.jbspin.2015.08.003. Epub 2015 Oct 6.

This article originally appeared on Clinical Pain Advisor.

Filed under: General Problems