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Muscle Relaxants Compared (Side Effects, Price)


In a previous article I have described and explained the various prescription muscle relaxants that are on the market in the U.S.

That article has received over 300 questions and comments. Therefore, I thought it was appropriate to now build on the information in that article with a new one:

A Comparison of Muscle Relaxants

Which Muscle Relaxant is the BEST?

It can be frustrating trying to find an effective combination of pain reliever and muscle relaxant to effectively deal with chronic pain. Your doctor prescribes a muscle relaxant. You get it filled. You try it. But it ends up being less effective than you hoped for, or maybe you experience a side effect that requires you to discontinue the drug. What next? In some cases a doctor will offer you an alternative muscle relaxer to try. Sometimes patients find it very difficult to encourage their physician to try again. I hope that the information in this article, comparing several prescription muscle relaxants, will provide you with some guidance and direction in speaking with your physician about your alternatives.

It is impossible to determine for any given patient which muscle relaxer will be the best. Some will respond better to one than another. The information provided here is intended to be a helpful resource as you make such decisions with your health care provider.

Note: Nothing in this article is intended to substitute for or replace the need for following the specific advice and direction of your physician. This article is intended to provide factual information on which to base your medical discussions.

When comparing muscle relaxants I will provide you with information from 3 perspectives:

  1. Muscle Relaxers Compared as to How They Work
  2. Muscle Relaxers Compared as to Their Side Effects
  3. Muscle Relaxers Compared as to Their Cost


Okay..this section is sort of for the science nerds. It contains some useful information, but if all you want to know is how they differ respecting Side Effects or Cost...feel free to skip down to the sections below.

First, to understand how Muscle Relaxants work in order to compare them, we first have to make a small distinction between "Spasticity" and "Spasm."

Spasticity, although a bit difficult to define, is best understood as a prolonged, involutary flexing of a muscle as often seen associated with conditions such as Multiple Sclerosis, spinal cord injury, cerebral palsey or stroke. In other words, it is typically the result of injury or diseases involving the brain.

Spasms are typically the result of more local conditions such as injury, fibromyalgia, or headaches.

These differences are reflected in the way we prescribe the various muscle relaxants. Some muscle relaxants are approved for "spasicity" conditions, while others are approved and used for more general "musculoskelatal conditions" and spasm.


A. Spasticity due to neurological disorders is often treated with drugs like:

  • Baclofen (works through an effect upon GABA receptors)
  • Dantrolene (blocks the release of calcium from muscle cells)
  • Tizanadine (a centrally-acting alpha 2 receptor agonist)

B. Spasms due to muskuloskelatal conditions are typically treated with drugs like:

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  • Carisoprodol
  • Chlorzoxazone
  • Cyclobenzaprine
  • Metaxolone
  • Methocarbamal
  • Orphenadrine

Another way to distinguish between muscle relaxants is by "where" they work. That is, some (actually all but 1) work within the Central Nervous System (CNS) and others (1 in particular) works directly on the contracting muscle.


1. Centrally Acting Muscle Relaxants.

These include:

  • Baclofen
  • Carisoprodol
  • Chlorzoxazone
  • Cyclobenzaprine
  • Diazepam
  • Metaxalone
  • Methocarbamal
  • Orphenadrine
  • Tizanadine

2. Direct Acting Muscle Relaxants.

These include:

  • Dantrolene


Now we can comapre muscle relaxers based upon side effects:

Amrix Side Effects - Click to Enlarge


Side effects from muscle relaxants can range from mild to serious. Often those dealing with chronic conditions find that the side effects from these prescriptions create significant problems with their daily lives. Therefore, a comparison of the side effects of popular muscle relaxants like Flexeril (cyclobenzaprine), Skelaxin (metaxalone), Soma (carisoprodol) and others may be helpful.

Comparing the side effects between muscle relaxants is challenging, as there have not been many studies which compares them all, under similar circumstances, to determine which effects are more likely with which drug.


Muscle relaxants, in general, have very few serious side effects. Here are a few mentioned in the literature:

  • Dantrolene has had some rare reports of liver damage
  • Tizanadine and Chlorzoxazone have had reports of liver toxicity.
  • Carisoprodol has quite a few reports of addiction, probably because it is metabolized into a controlled substance (meprobamate).


As for the more common side effects like drowsiness, dizziness, dry mouth, headache, etc. we can see them in all products. It is very difficult to compare muscle relaxants with respect to their side effects. Part of the reason is that studies do not always report the "%" of patients experiencing a side effect, thus it is difficult to compare between studies which side effects are most frequent with which drugs.

Below is a brief list of some of the more common side effects with my opinion (based upon studies AND interaction with patients) as to which are the most notable culprits:

Dry Mouth (also known as xerostoma): Many patients complain of dry mouth with muscle relaxants. Typically cyclobenzaprine (i.e. Flexeril, Amrix) and tizanadine are the most likely to cause this side effect. Sucking on hard candy may help, but if not, consider talking to your doctor about an alternative if this has become especially bothersome. Most of the other muscle relaxants rarely report this side effect.

Drowsiness: Again, most muscle relaxers could cause drowsiness, dizziness and sedation. Cyclobenzaprine and tizanadine tend to be very sedating. For alternative that tend to be less sedating, talk to your doctor about metaxalone or chlorzoxazone.

Nausea: All muscle relaxers have been reported to cause some nausea. Taking them with food may help decrease this side effect. If nausea becomes a problem, consider talking to your doctor about a milder muscle relaxant like methocarbamal.


Finally, a comparison of prescription muscle relaxers should make some mention of the costs. All are available generically, however if you have to pay for these yourself it can still be rather pricey.

Muscle Relaxer Prices - Retail Pharmacy Prices

This table compares the actual retail price of various prescription muscle relaxers for 1 particular local pharmacy. Prices may vary in your area, but this clearly shows which are the LEAST and MOST expensive prescription muscle relaxants.

Drug NameQuantityCost

Cyclobenzaprine 10mg



Carisoprodol 350mg



Tizanadine 4mg



Chlorzoxazone 500mg



Baclofen 10mg



Diazepam 5mg



Amrix 30mg (generic)



Skelaxin 800mg (generic)



Methocarbamal 500mg



As seen from the above table - all prescription muscle relaxers are NOT priced similarly.

The price WINNERS (lowest cost) are clearly Flexeril (cyclobenzaprine), Diazepam, Baclofen and Chlorzoxazone. These have the lowest relative cost if you have to pay for them yourselves. Of course, if you have insurance and pay the same copay for ANY generic...then these prices do not matter to you so much (unless you have a benefit limit).

Medium priced muscle relaxers might be Soma (carisoprodol) and Robaxin (methocarbamal).

HIGH priced products include Zanaflex (tizanadine), Amrix (cyclobenzaprine ER) and Skelaxin.


Choosing a muscle relaxant involves balancing many factors including your diagnosis, the mechanism, the side effects and the cost. I hope this article has given you some information to help discuss this category of medications with your MD.

Have a question? Feel free to ask below. I try to respond to all questions.

© Jason Poquette RPh


Alicia on October 13, 2017:

Why is my tongue swollen

Andrea on December 11, 2014:

I actually have several conditions that warranted the need for them, otherwise I probably wouldn't have been on them for so long. I don't know about your state laws, they must be different than ours. I moved twice which caused me to switch doctors both times and they still prescribed them to me each month. Obviously, I took soma for 6 years because it was needed. I'm currently on a different medication because the laws in our state recently changed concerning soma.

I just wanted an opinion on which medication worked as well as what i had been taking because with all of my conditions I'm in pain every day and have been for most of my life, but thank you for questioning my need for it instead of what would help me.

MK on November 16, 2014:

Soma should never be prescribed for more than 14 days. No one needs a muscle relaxant every day, day after day, for years(unless you have spasticity caused by neurological condition). I do not prescribe soma for my patients. Why would you take soma for 6 years? Where I practice prescribing soma for that long will get you audited by licensing agencies.

Andrea on October 25, 2014:

I've been on soma for about 6 years, but now my doctor is no longer prescribing it, along with several other doctors following suit. Zanaflex and robaxin do nothing to help me, and I do not want Valium. I'm also currently on a pain medication as well. What would you recommend that works as well as soma? Please help!

Jason Poquette (author) from Whitinsville, MA on December 10, 2013:


A systolic BP over 200 should be immediately addressed with medical intervention. Please do so. Best wishes.

kristina on December 01, 2013:

Have been on high doses of tizanadine. Just switched to lorzone. My BP is over 200. Is this normal and will it adjust and how soon.

fenix on January 13, 2013:

I have fibro and my cymbalta dose schedule is 60mg at bedtime, 30mg in the morning, and another 30mg in the afternoon. It sounds like you may need a higher dose of cymbalta or more doses throughout the day. I would try that before adding more different drugs to your cocktail.

Jason Poquette (author) from Whitinsville, MA on June 29, 2012:


Valium has a higher potential for addiction, and given that you are on Vicodin already, the MD is trying (I imagine) to limit the exposure of your body to other substances that can cause too much dependence. Personally, if you can achieve a reasonable quality of life using Soma, I would stick with it. Valium is not "better" although some people are helped by it also.

Sarah on June 26, 2012:

Hi, I am being treated for Fibromyalgia, osteoarthritis, and TMJ. Flexeril did nothing for me, I had a severe allergic reaction to Parfon Forte, and am currently on Soma. (also 60mg of Cymbalta, 10mg of Zolpidem and Vicoden -varying doses as pain flares up and goes down - if that helps). I noticed taking half of a Zolpidem works the best, without making me sleepy, and I think Valium is simlar and may work better than the Soma, but my doctor is reluctant to try. Do they have similar effects? Could Valium possibly work better than the Soma? Thank you.

Jason Poquette (author) from Whitinsville, MA on June 18, 2012:


Soma was moved to Class IV in many states. But that should not prevent you from getting it.

Steve on June 16, 2012:

I was on Soma, but they moved it to a class II, tried cyclobenzaprine, metaxalone and baclophen, none of these equal Soma, any suggestions? Need something that works as well as Soma, thanks.

Jason Poquette (author) from Whitinsville, MA on February 24, 2012:


Thank you for the vote - and also for sharing your experience! Glad that your relationship with muscle relaxers was brief. Best wishes.

Dianna Mendez on February 23, 2012:

Very informative and educational hub on muscle relaxers. I especially like your price comparison post. Also helpful are your suggestions in dealing with side effects. I have only had to take muscle relaxers once and that was when I pulled a muscle in my back. It helped me relax enough to allow my muscle to gain strength. I am thankful that I only had to take it for about a week though because it did make me drowsy. Voted up!

LTaylor99 from USA on February 22, 2012:

Lovely explanation!

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