Pain Management: Why Do We Keep Doing the Wrong Things?

April 29, 2014

The concomitant prescribing of opioid analgesics and benzodiazepines is not supported by science. So why is it still a common practice?

For years I have heard many health care professionals claim that the reason we are doing such a poor job managing chronic pain is primarily the result of a single factor: physicians’ fear of the possible legal consequences of prescribing opioids.

Whenever I have heard this, I have responded that this is easy to disprove. There are many common pain conditions such as neuropathic pain, including diabetic neuropathic pain and postherpetic neuralgia, that respond far better to non-opioids, such as antiepileptics and serotonin-norepinephrine reuptake inhibitors, as well as other conditions such as fibromyalgia, for which opioids provide little benefit. Yet the pain from these conditions is just as poorly managed as pain that responds best to the opioids.

Furthermore, the number of prescriptions for opioids continues to climb in this country, but there is nothing to indicate that there is any commensurate improvement in the care of patients with pain.

I have long held the belief that pain management is not adequately covered in medical school and postgraduate training, leading to pain being poorly managed by physicians in practice.

A new study recently presented at the annual meeting of the American Academy of Pain Medicine strongly supports my view.1

Using a national database of 3.1 billion visits to primary care physicians, the study authors found that in the 6-year period from 2002 to 2008, the number of patients receiving prescriptions for both benzodiazepines and opioids increased by 12% each year. Overall, there was a 12.5% increase in prescriptions for benzodiazepines and a 9.6% increase for opioids per year.

With very rare exception, there is really no reason for physicians to be prescribing both benzodiazepines and opioids for the same patient, and in fact, a host of reasons to not prescribe them together.

To begin with, the combination can be quite dangerous. Both opioids and benzodiazepines have been found to be commonly involved in unintentional drug overdoses. A study published last year showed that in almost 30% of opioid overdose deaths, a benzodiazepine was also being taken.2

Despite this, the new study found that during the period examined, there was a 6.4% per year increase in the number of prescriptions for opioids in combination with benzodiazepines provided in emergency departments, the places where one might expect the staff to be most attuned to the problems associated with prescribing these two classes of drugs together.

The potential danger of the combination aside, prescribing a benzodiazepine for a patient taking an opioid for pain makes little sense, since benzodiazepines can interfere with the analgesic effects of opioids.3 Giving a benzodiazepine may simply lead to a need for increased doses of opioids to get the same analgesic effect, something we would like to avoid.

Even if a patient is not taking an opioid, it is generally not a good idea to prescribe a benzodiazepine for patients with pain.

Extended use of benzodiazepines can lead to hyperalgesia, which causes a lowering of the pain threshold. As a result, there are patients whose pain can be significantly reduced by simply discontinuing the benzodiazepine.

Stopping benzodiazepines, however, may be problematic, since these agents can be quite addicting; therefore, patients may resist stopping their use of them. In fact, in my clinical experience treating patients with pain who have developed a psychological dependence on opioids and benzodiazepines, I have usually found there is much less resistance to discontinuing the former than the latter.

The indications for benzodiazepines are few. Most clinical guidelines on the treatment of anxiety disorders recommend initiating treatment with the antidepressants that also act as anxiolytics. Some of these antidepressants have the additional benefit of being excellent analgesics.

The only benefit of benzodiazepines is that they may work more quickly, but in treating a chronic disorder, this would be of relatively little importance and therefore not very useful. They may be of use for acute, time-limited episodes of anxiety, such as those that might be related to a life stressor that would be expected to resolve within a few weeks at most.

As far as prescribing benzodiazepines for insomnia, as is still commonly done, again clinical guidelines generally recommend against this. The non-benzodiazepine sedative hypnotics, such as zolpidem (Ambien), zaleplon (Sonata), and eszopiclone (Lunesta), appear to be much better choices for treating this problem.

Although benzodiazepines are frequently prescribed for patients with pain as muscle relaxants, there is limited literature to support this practice. Whether they really provide much direct muscle relaxation or the benefits are primarily a result of their sedating effects is open to question.

The overuse of benzodiazepines among patients with pain is not a new problem. Almost 25 years ago I co-authored a study that identified this same issue.4

Why Do Patterns Persist?
There are only 3 possible reasons I can think of why primary care doctors are continuing to prescribe benzodiazepines for patients who also take opioids, and are doing so with increasing frequency, despite all the evidence indicating that this is a poor choice: They are purposely ignoring this evidence, feel that it is incorrect, or are unaware of it.

Although there may be physicians who don’t care about their patients and are willing to prescribe anything for money, I believe it is a very small number. However, as I write this, there is a physician on trial for manslaughter in New York who made $450,000 in 2 years from a 1-day-per-week, cash-only practice where he primarily prescribed oxycodone and alprazolam (Xanax). Several of his patients died of overdoses.

I’m also unaware of anything to indicate that the doctors prescribing the combination believe that the evidence against doing so is flawed.

So, that leaves physicians’ ignorance. And the only thing that can change that is improved education.

References:

1. Kao MC, Zheng P, Mackey S. Trends in benzodiazepine prescription and co-prescription with opioids in the United States. Presented at: 30th Annual Meeting of the American Academy of Pain Medicine; March 6–9, 2014; Phoenix.

2. Jones CM, Mack KA, Paulozzi LJ. Pharmaceutical overdose deaths, United States, 2010. JAMA. 2013;309:657-659.

3. Gear RW, Miaskowski C, Heller PH, et al. Benzodiazepine mediated antagonism of opioid analgesia. Pain. 1997;71:25-29.

4. King SA, Strain JJ. Benzodiazepine use by chronic pain patients. Clin J Pain. 1990;6:143-147.