Muscle Relaxant For Low Back Pain

Treatment Ratings


RISK: 3/5


Common side effect include sedation, weakness or fatigue, dizziness, and dry mouth. Less common risks include confusion, lethargy, and “anticholinergic” side effects., Some are toxic in overdose and when combined with other substances. Carisoprodol (Soma) is felt to have the highest risk of dependence and abuse, and for that reason some researchers have called for it to be classified as a controlled substance.

Researchers cannot yet determine if one type of muscle relaxant is “safer” than another, though some studies have indicated a higher risk for abuse and addiction with carisoprodol, and tizanidine and chlorzoxazone have been associated with usually-reversible liver toxidity in studies.

Most have side effects which include varying degrees of drowsiness, though some less than others. Carisoprodol is considered a Class IV drug by some states due to its potential for dependence and withdrawal potential. Other drugs such as cyclobenzaprine should be used with caution in patients with heart disease.

From Choosing a Skeletal Muscle Relaxant: SHARON SEE, PharmD, BCPS, and REGINA GINZBURG, PharmD, St. John’s University College of Pharmacy and Allied Health Professions, Jamaica, New York

Am Fam Physician. 2008 Aug 1;78(3):365-370.

Chou 2005 Drug Class Review on skeletal muscle relaxants




Although guidelines recommend acetaminophen (Tylenol) and non-steroidal anti-inflammatory drugs (NSAIDS) like Ibuprofen or naproxen as first line therapy, many physicians routinely prescribe muscle relaxants as well. The research shows that muscle relaxants are better than placebo, but not more effective than NSAIDS for patients with acute low back pain.

In fact, there isn’t a lot of great research on muscle relaxant effectiveness. Most of the existing studies are old and not necessarily well done, and since many are now off patent, there is little incentive for drug companies to do new studies. Nevertheless, they are widely used for back pain.

Studies comparing hour well one muscle relaxant works versus another have generally only been of fair quality. Published comparison studies suggest cyclobenzaprine (Flexeril) is more effective than other muscle relaxants like diazepam, but the differences between drugs was small. While the studies were only of fair quality, they do show that muscle relaxants are more effective than placebo. Exactly how they work to help patients with back pain is not understood, but part of the effect may be due to the sedating effects of these drugs.

Interestingly, some drugs, like Valium (Diazepam) are used as muscle relaxants although they are not approved by the FDA for this purpose.

Most guidelines suggest muscle relaxants work best in the first few days, and should not be used for more than 2-3 weeks.

Chou 2005,

From Choosing a Skeletal Muscle Relaxant: SHARON SEE, PharmD, BCPS, and REGINA GINZBURG, PharmD, St. John’s University College of Pharmacy and Allied Health Professions, Jamaica, New York

Am Fam Physician. 2008 Aug 1;78(3):365-370. See, 2008




Muscle relaxants are prescription drugs and can only be obtained from an MD or DO, or through their physician assistant (PA-C) or nurse practitioner partners.


COST: 4/5


Costs for muscle relaxants vary widely, though most are covered by insurance plans. You can pay as little as $5 to $15 for a 2 week supply, or as much as $100 or more. In addition, there are various dosages for many brands, though there is little scientific evidence that one dose is more effective than another. The same holds true for the extended release or other versions of the drug.

Drug costs can vary wildly. Popular versions that have been around a while (or have generic equivalents) may be fairly inexpensive, but manufacturers will sometimes change the dosage and dramatically increase the price.

One recent Google search yielded the following prices, not counting any discounts for insurance:


DRUG                                              DOSAGE                                PRICE             QUANTITY

Cyclobenzaprine                             10mg                                       $9                            90

Cyclobenzaprine                             15mg                                     $919                          30

Carisoprodol (Soma)                      350mg                                    $13                           90

Methocarbamol (Robaxin)            750mg                                    $15                           90

Metaxolone (Skelaxin)                    800mg                                  $77                           30

Orphenadrine ER                            100mg                                    $32                           60


USEFULNESS (overall rating): 2/5


Though widely used, as noted, the exact mechanism for how muscle relaxants is not yet known. Studies show they are no more effective than NSAIDS in treating pain, and combining them with NSAIDS is not more effective than NSAIDs alone for pain. While muscle relaxants are among the most widely prescribed drugs for musculoskeletal conditions, medical experts note that these should generally not be the first line drugs used for these conditions.

They are however relatively safe and inexpensive, and may help reduce pain or spasm in low back conditions. However, this must be balanced with their sedating risks (don’t drive while taking these!) and other risks of heart, liver or kidney problems.

Based on these factors, we rate muscle relaxants


Chou R, Peterson K, Helfand M.  Comparative efficacy and safety of skeletal muscle relaxants for spasticity and musculoskeletal conditions: a systematic review. Journal of Pain and Symptom Management 2004; 28(2): 140-175.



[hwh_sidebar_latest_posts num_posts=3]


[hwh_sidebar_top_posts num_posts=3]


Spinal Infection

Overview Spinal infections involve the: Intervertebral disc space Spinal canal Surrounding soft tissue Vertebral column The infections, bacteria or fungal can present 3 days to 3 months after surgery. Intervertebral disc space infections are between two vertebrae. Disc space infections are classified into 3 subcategories: Discitis (childhood) Postoperative Spontaneous (adult hematogenous or blood-borne) Vertebral Osteomyelitis is…
Read More

Spinal Cancer

What is Spinal Cancer? Overview Spinal cancer involves tumors or masses of abnormal cells originating in spinal tissue or brain (also known as spinal tumors).  Primary tumors may start due to certain inherited gene mutations. Those that metastasize or spread to the spine from other body areas are secondary spinal tumors. Typically they come from…
Read More

Stay in Shape During COVID-19

Corona Virus, COVID-19: Restricted to shelter at home: What can you do to stay in shape? With the shelter in place happening all over the world, you may be asking yourself what you can do to stay in shape or at least continue to manage your health, fitness and in some cases, your rehab while…
Read More