Muscle Relaxants Ineffective for Low Back Pain and Fibromyalgia

By Pat Anson

Muscle relaxants are increasingly prescribed “off label” as an alternative to opioid medication, but according to a new analysis they are no more effective than a placebo in treating fibromyalgia and low back pain. They may be beneficial, however, for patients suffering from muscle cramps, neck pain and trigeminal neuralgia.

Researchers reviewed 44 studies involving nearly 2,500 patients who were prescribed a muscle relaxant for various pain conditions. Nine skeletal muscle relaxants (SMRs) were assessed, drugs that were initially developed and then approved by the FDA as anti-spasticity and anti-spasmodic medications:

• Carisoprodol (Soma)

• Baclofen

• Tizanidine

• Cyclobenzaprine

• Eperisone

• Quinine

• Orphenadrine

• Chlormezanone

• Methocarbamol

Despite a lack of evidence on their effectiveness beyond 3 weeks, prescribing of SMRs doubled between 2005 and 2016, with office visits for refills of SMR prescriptions tripling over the same period, indicating they were increasingly being used long-term and off-label. According to a 2021 study, over a third of patients prescribed SMRs did not have a musculoskeletal disorder, a sign of “unnecessary or inappropriate use.”

Researchers involved in the current study, published in JAMA Network Open, reached a similar conclusion that muscle relaxants are overprescribed.

“Despite increasing prevalence and increasing risks of their use, our systematic review suggests only limited evidence of efficacy for long-term use of SMRs for a small subset of pain syndromes,” wrote lead author Benjamin Oldfield, MD, an Assistant Clinical Professor of Internal Medicine at Yale School of Medicine.

“Evidence for effectiveness was strongest for SMRs used for muscle spasms, painful cramps, and neck pain; in studies of SMRs for fibromyalgia, low back pain, headaches, and other syndromes, some showed small benefits and some did not, and on balance studies did not suggest a benefit.”

Oldfield and his colleagues say physicians should consider deprescribing SMRs to pain patients who have been using them long-term without apparent benefit.   

Adverse side effects from SMRs include sedation, somnolence, dizziness and dry mouth. The FDA also warns against taking the drugs with opioids, which could raise the risk of respiratory depression and overdose.

SMRs also increase the risk of falls, fractures, and vehicle crashes. Because of those risks, muscle relaxants should be avoided altogether in elderly patients, according to the American Geriatrics Society.

Medical Cannabis Linked to Rebound Headaches

By Pat Anson, PNN Editor

Medication overuse headache, also known as “rebound” headache, is a common problem for people who frequently use pain medication to relieve headaches and migraine.

According to the American Migraine Foundation, rebound headaches can be triggered by a wide assortment of analgesics, from aspirin and triptans to acetaminophen and opioids. Even caffeine can cause a rebound headache if you consume more than 200mg a day – about two cups of coffee.     

So perhaps it’s not surprising that medical cannabis is also associated with medication overuse headache, according to a preliminary study by researchers at Stanford University School of Medicine.

“Many people with chronic migraine are already self-medicating with cannabis, and there is some evidence that cannabis can help treat other types of chronic pain,” said study author Niushen Zhang, MD, a neurologist who is director of Stanford’s Headache Fellowship Program.

“However, we found that people who were using cannabis had significantly increased odds of also having medication overuse headache, or rebound headache, compared to people who were not using cannabis.”

Zhang and her colleagues looked at the medical records of 368 people who had chronic migraine -- which is 15 or more headache days per month. Less than half were using medical cannabis

Researchers found the cannabis users were six times more likely to have rebound headaches than those who did not use cannabis. People who used cannabis were also more likely to take opioids.  Previous research has found that opioids and cannabis can both influence the part of the brain called the periaqueductal gray, which has been linked to migraine.

Zhang’s study will be presented at the American Academy of Neurology’s annual meeting next month.

Medical cannabis has become a trendy alternative to pharmaceuticals for treating migraine, with research showing that both inhaled and ingested cannabis can reduce migraine pain. 

A recent study of nearly 10,000 people in the U.S. and Canada who used a migraine tracking app found that 82 percent who used cannabis believed it was an effective pain reliever.    

A 2017 study conducted in Israel found that combining THC and CBD in an oral dose was just as effective in treating migraine pain as amitriptyline – a tricyclic antidepressant commonly prescribed for migraine.

And a 2016 study at the University of Colorado found that cannabis significantly reduced the number of migraine headaches. Inhalation appeared to provide the fastest results, while edible cannabis took longer to provide pain relief.

About a billion people worldwide suffer from migraine headaches, which affect three times as many women as men. Over 37 million people in the United States live with migraines, according to the American Migraine Foundation.

Do Smartphones Cause More Headaches?

By Pat Anson, PNN Editor

People with headaches who use smartphones are more likely to use more pain medication, but get less relief from the drugs, according to a new study conducted in India.

Researchers surveyed 400 people who suffer from a primary headache condition, which includes migraine, tension headache and other types of headaches, asking them about their smartphone and medication use.

The smartphone users were more likely to take pain-relieving drugs for their headaches than non-users, with 96% of smartphone users taking the drugs compared to 81% of non-users. Smartphone users took an average of eight pills per month compared to five pills per month for non-users.

Smartphone users also reported less relief from pain medication, with 84% gaining moderate or complete relief of headache pain compared to 94% of non-users. The study findings were published in the journal Neurology Clinical Practice.

"While these results need to be confirmed with larger and more rigorous studies, the findings are concerning, as smartphone use is growing rapidly and has been linked to a number of symptoms, with headache being the most common," said lead author Deepti Vibha, DM, of All India Institute of Medical Sciences.

The study has limitations. It only examined people at one point in time and did not follow them over an extended period. It also relied on people to self-report their symptoms and use of pain medication.

While the study does not prove that smartphone use causes headaches or greater use of pain medication, it does show an association.

“There is a great deal of speculation among the lay population regarding the effect of computers and mobile phones on ailments such as headaches and neck pain. However, although there are anecdotal stories suggesting a link between technology use and pain, there is little evidence of either a definitive relationship or data absolving mobile phones or computers from a link to recurrent pain,” wrote Heidi Moawad, MD, of Case Western Reserve University, in an editorial accompanying the study.

“Smartphone users may rely on the devices for many hours per day -- while on the go, resting, or working -- which puts a strain on the eyes, neck, and back. As people are becoming more dependent on these devices, it would be worthwhile to know whether using smartphones could lead to health problems.”

A 2017 study speculated that high energy visible (HEV) light – also known as blue light – emitted by smartphones, laptops, desktop computers and other digital devices could contribute to headaches by causing eye strain. Blue light has a very short wavelength that penetrates deep into the eye.

A nationwide survey of nearly 10,000 adults by The Vision Council found that about a third had symptoms of digital eye strain, including neck and shoulder pain, headache, blurred vision and dry eyes.

More information about blue light can be found at BlueLightExposed.com.