Flexeril and methocarbamol are two of the most common skeletal muscle relaxants. Because of this, people assume these prescription medications are harmless.
Yet, both Flexeril and methocarbamol affect your central nervous system. They’re similar to other CNS depressants, like alcohol and opioids, and should be taken more seriously.
So, if you’re choosing between Flexeril and methocarbamol, you should always consider the adverse effects.
In this article, we compare Flexeril vs. methocarbamol and show you why your choice matters.
What Is Flexeril?
Flexeril and Amrix are brand names for cyclobenzaprine, an FDA-approved skeletal muscle relaxant. The brand-name Flexeril tablet was discontinued in the United States years ago, so what you get at the pharmacy today is generic cyclobenzaprine, even if your doctor still calls it Flexeril.
What makes cyclobenzaprine different is its mechanism of action. It doesn’t work directly on your skeletal muscles. Chemically, it belongs to the same drug class as older tricyclic antidepressants, and it acts in the brainstem on serotonin pathways to calm the nerve signals that drive muscle spasms. That tricyclic structure is also why it has anticholinergic side effects like dry mouth and constipation.
Cyclobenzaprine reduces muscle hyperactivity to treat muscle spasms and other acute musculoskeletal conditions. It is also prescribed off-label for fibromyalgia.
Flexeril Side Effects
Flexeril or cyclobenzaprine has several side effects. The most common side effects include the following.
- Constipation
- Drowsiness
- Dry mouth
Serious side effects of cyclobenzaprine include:
- Heart rhythm changes
- Difficulty breathing and lightheadedness
- Allergic reactions
What Is Methocarbamol?
Methocarbamol is the generic name for Robaxin, an FDA-approved central nervous system depressant. Its exact mechanism of action isn’t fully understood, but it appears to dampen reflexes in the spinal cord, calming overactive nerves to treat muscle pain.
Robaxin is most often prescribed for acute low back pain and neck strain. An injectable form is also used in hospitals for the muscle spasms caused by tetanus (lockjaw).
Methocarbamol Side Effects
Methocarbamol or Robaxin may cause the following side effects.
- Drowsiness
- Blurred vision
- Upset stomach
In serious cases, Robaxin may also cause:
- Confusion
- Shallow breathing
- Hives and facial swelling
Flexeril Vs. Methocarbamol: A Side-By-Side Comparison
While Flexeril (cyclobenzaprine) and Robaxin (methocarbamol) have similar side effects, the way they work in your body has key differences. Understanding these differences can help you avoid unnecessary risks.
Quick Overview
| Flexeril | Robaxin | |
| Generic Name | Cyclobenzaprine | Methocarbamol |
| Usage | Short-term use; best for nighttime | Short-term use; best for daytime |
| Sedative Effects | More sedating, for acute muscle spasms | Less sedating for musculoskeletal pain |
| Strength and Dosage | Fewer daily doses needed | Higher doses needed |
| Drug Interactions | More known drug interactions | Fewer drug interactions |
| Misuse Potential | Higher misuse potential | Lower misuse potential |
| Cost | Generic only (brand discontinued); inexpensive | Generic and brand available; inexpensive |
1. Usage
Flexeril and methocarbamol are both muscle relaxers and antispasmodics. They control muscle contractions and are effective for pain relief.
Neither one is meant to be the whole treatment. Both are approved as an add-on to rest and physical therapy for a couple of weeks, not as a long-term fix. A review in American Family Physician, written by two PharmD pharmacists, found that muscle relaxants work modestly better than placebo for short-term relief, with no clear winner between them.
The main difference is that Flexeril has stronger effects on your cognition. It can make you drowsy and confused. Because of this, Flexeril is best used at night.
In comparison, methocarbamol is better for mornings, when you need to stay alert.
2. Sedative Effects
Flexeril gets prescribed when stronger sedation is necessary. It’s more useful as an antispasmodic due to its sedative effects.
On the other hand, methocarbamol isn’t as strong in terms of sedation. This makes it suitable to treat muscle pain and other acute musculoskeletal conditions.
3. Strength and Dosage
Flexeril has stronger effects than methocarbamol, and it stays in your system much longer.
Immediate-release cyclobenzaprine has a half-life of around 18 hours, meaning it takes that long for your body to clear half of the dose. The extended-release capsule (Amrix) stretches that to roughly 32 hours, so it only needs to be taken once a day. The regular tablet is usually taken up to three times daily.
On the flip side, the milder methocarbamol has a half-life of only one to two hours. You need to take it four times daily for consistent pain relief.
4. Drug Interactions
Both Flexeril and methocarbamol are generally safe on their own. However, you have to be careful if you’re taking other prescription medications.
Flexeril is less compatible with other substances. It interacts with 453 other drugs. Meanwhile, methocarbamol interacts with 348 other drugs.
Never take these medications with alcohol, opioids, or sleeping aids. Otherwise, you may experience stronger side effects, such as drowsiness and difficulty thinking.
Cyclobenzaprine carries one extra risk because of its effect on serotonin. Combined with antidepressants (SSRIs, SNRIs), tramadol, or supplements like St. John’s wort, it can trigger serotonin syndrome, a rare but dangerous reaction that causes agitation, rapid heartbeat, and high fever.
Over-the-counter pain relievers like acetaminophen (Tylenol) and ibuprofen are generally fine to take alongside either drug, and doctors often pair them. Still, mention everything you take to your doctor or pharmacist, including supplements.
5. Misuse Potential
Lastly, both Flexeril and methocarbamol have low risks for addiction. That said, they can be misused due to their sedative effects.
Flexeril has a higher potential for misuse than methocarbamol because of its relaxing properties. Some people may combine it with alcohol, antidepressants, or other drugs to increase the effects.
For context, neither drug is a controlled substance. The muscle relaxant with the worst track record is carisoprodol (Soma), which the DEA schedules because it breaks down into a sedative with real abuse and withdrawal risk.
Other Muscle Relaxants You Might Be Offered
Flexeril and methocarbamol aren’t the only options, and some alternatives are meant for very different problems:
- Tizanidine (Zanaflex) and baclofen are antispastic drugs. They treat spasticity, the stiff, tight muscles caused by nerve damage in conditions like multiple sclerosis or spinal cord injury, rather than a strained back.
- Diazepam (Valium) relaxes muscles too, but it’s a benzodiazepine with a high dependence risk, so it’s rarely a first choice.
- Metaxalone (Skelaxin) is the least sedating of the group, but it’s also the most expensive and has the weakest evidence.
- Carisoprodol (Soma) works, but for the reasons above it’s a poor choice for anyone with a history of substance use.
Flexeril Vs. Methocarbamol: Cost and Insurance Coverage
Cost rarely decides this one, because both drugs are cheap generics. Still, there are a few things worth knowing before you fill the prescription.
Generic availability. Brand-name Flexeril is no longer sold, so every cyclobenzaprine prescription is generic by default. Methocarbamol is available as both generic methocarbamol and brand-name Robaxin, and there’s no reason to pay for the brand.
Average retail cost. Without insurance, a 30-tablet supply of generic cyclobenzaprine 10 mg runs roughly $20 to $55 depending on the pharmacy, and 30 tablets of methocarbamol 500 mg runs about $17 to $27. Free coupons from pharmacy discount programs regularly bring either one under $10. The outlier is the extended-release capsule (Amrix), which can cost several hundred dollars a month even as a generic.
Insurance coverage. Both generics sit on the lowest copay tier of most commercial plans and Medicare Part D formularies. One catch for people over 65: both drugs appear on the American Geriatrics Society Beers list of medications to avoid in older adults, so some Medicare plans ask for prior authorization or limit the quantity.
Dosages. Because methocarbamol is taken four times a day at 500 mg to 1,500 mg per dose, a prescription uses far more tablets than cyclobenzaprine at 5 mg to 10 mg up to three times a day. That evens out the per-tablet price difference, which is why the monthly cost comparison usually lands within a few dollars either way.
Can You Become Addicted to Flexeril and Methocarbamol?
Flexeril and methocarbamol aren’t addictive like opioids or benzodiazepines. Yet, you can still become psychologically dependent on them after long-term use.
Those who abuse Flexeril and methocarbamol experience increased tolerance. They need more of the drug to feel the same effects.
It’s possible to experience withdrawal symptoms once you’re dependent on Flexeril and methocarbamol.
Should You Use Flexeril or Methocarbamol?
In general, Flexeril is best when you’re experiencing severe muscle spasms and fibromyalgia. Meanwhile, methocarbamol is better for pain relief during the day.
Before using Flexeril or methocarbamol, you should first seek medical advice. Your doctor will be able to tell you which is better for your medical conditions. Additionally, they will prescribe you the lowest recommended dose to avoid dependence.
When Should You Stop Taking Flexeril or Methocarbamol?
Flexeril and methocarbamol are both for short-term usage. Prolonged use can lead to dependence.
If you’re experiencing any of these symptoms, it’s a sign that you need to ask your doctor to switch your medication.
- You can no longer sleep or relax without your medication.
- You feel irritable or uncomfortable without Flexeril or methocarbamol.
- You take Flexeril or methocarbamol to fight anxiety, and you’re constantly thinking about the next dose.
Recovering From Flexeril or Methocarbamol Dependence – How We Can Help
Dependence on Flexeril or methocarbamol can happen without you realizing. What starts as a prescription medication can slowly turn into a way to cope with stress.
If you find yourself taking more Flexeril or methocarbamol than you should, don’t worry. Recovery is possible with the proper assistance.
Long Island Treatment Center is a drug and alcohol rehab center that can help you overcome your battle with addiction. We’ll provide you with everything you need so you can start living life worry-free.
Here’s what you can expect at our facility.
1. Pain-Free Detox
Experiencing the withdrawal symptoms is sometimes the most difficult part of recovery. Long Island Treatment Center ensures your safety and comfort through medication-assisted treatment (MAT).
In MAT, we use prescription medication to ease your symptoms and lessen your cravings. This helps prevent possible relapses.
2. Compassionate Healthcare Professionals
We genuinely care for your well-being. That’s why we only work with the most experienced and compassionate healthcare providers.
At our facility, you’ll experience judgment-free, compassionate care from people who understand.
3. Private Rooms
We believe that a patient’s environment has a direct effect on their recovery. That’s why the Long Island Treatment Center prioritizes your peace.
Expect comfortable and private rooms away from the hustle and bustle of New York City. You’ll feel right at home with us.
4. Flexible Treatment Options
Long Island Treatment Center understands that not everyone has the time or resources to seek treatment. We make sure to offer flexible options for those who can’t commit to 24/7 residential care.
- Outpatient Rehab: Outpatient rehab is an affordable option that only requires a few hours of commitment per week. Under this program, you’ll be able to continue working without anyone realizing that you’re seeking treatment.
- Intensive Outpatient Program: The intensive outpatient program offers more support than the regular outpatient program. It’s an effective treatment for patients dealing with more severe addictions.
- Partial Hospitalization Program: The partial hospitalization program is an in-depth treatment that requires more hours. However, you still have the freedom to return to your home after your sessions.
5. Tailored Therapies
Long Island Treatment Center uses evidence-based therapies designed to help you recover from any addiction. We always tailor our treatments to your specific needs to achieve the best possible outcome.
- Rehab for Young Adults: We take a different approach for teenagers and young adults, focusing on social stigmas, pressure, and depression.
- Rehab for Women: In many cases, women experience certain traumas that can lead to addiction. We provide everything you need to get help, including medical support and childcare.
- Rehab for Seniors: Recovery can be challenging for seniors with physical health restrictions. We take special care to ensure your safety and comfort throughout the healing process.
- Rehab for Professionals: Long Island Treatment Center has the capabilities to keep treatment discreet for professionals. We know how to work around your schedule to ensure your full recovery.
6. World-Class Standards
Long Island Treatment Center has the highest standards when it comes to addiction recovery. Our center is recognized for excellence in substance abuse and behavioral health treatment by the Joint Commission.
This means you get the best quality of care from the most knowledgeable professionals. We’re here to help you get through the toughest time of your life.
Conclusion
Flexeril and methocarbamol are both commonly prescribed muscle relaxers. Yet, they have differences that matter.
Flexeril is a stronger muscle relaxant that has a higher potential for abuse and dependence. Methocarbamol is milder and suitable for those experiencing pain. That said, you can still build a tolerance when you misuse it.
It’s best to seek advice from your doctor to determine which medication is best for your needs.
Lastly, if you’re struggling with Flexeril and methocarbamol dependence, please don’t hesitate to reach out to us. Long Island Treatment Center is here to provide you with the guidance you need to regain control over your life.