What is muscle relaxant ?

If you have neck or back pain, or you’re dealing with some other condition that causes muscle spasms, your doctor might prescribe a muscle relaxer (or muscle relaxant) for you.Muscle spasticity, on the other hand, is a continuous muscle spasm that causes stiffness, rigidity, or tightness that can interfere with normal walking, talking, or movement. Muscle spasticity is caused by injury to parts of the brain or spinal cord involved with movement. Conditions that can cause muscle spasticity include multiple sclerosis (MS), cerebral palsy, and amyotrophic lateral sclerosis (ALS).

Prescription drugs can help relieve the pain and discomfort from muscle spasms or spasticity. In addition, certain over-the-counter medications may be used to treat aches and pains associated with muscle spasms.

When You Might Need a Muscle Relaxer

Your doctor might first suggest you try an over-the-counter medicine like acetaminophen (Tylenol) or ibuprofen (Advil) to treat your pain. But if those don’t work, or you can’t take them because you have another issue like liver problems or ulcers, you may need to try a muscle relaxant.

Muscle relaxants are ideally prescribed for acute rather than chronic pain. They may be an option if pain is preventing you from getting enough sleep. Because muscle relaxants cause drowsiness, they can help you get rest when you take them at night.

Side Effects

No matter what kind of muscle relaxer you take, you’ll experience one or more side effects. Some muscle relaxants, however, can have potentially serious side effects, like liver damage. Your doctor will work with you to find the medication that makes the most sense for your situation.

The most common side effects include:

      • Tiredness, drowsiness, or sedation effect
      • Fatigue or weakness
      • Dizziness
      • Dry mouth
      • Depression
      • Decreased blood pressure

You shouldn’t drink alcohol while taking muscle relaxants. These medications make it hard to think and function normally, even if you take a low dose, so combining them with alcohol can increase your risk of an accident.

You also shouldn’t drive or operate heavy machinery while taking muscle relaxants. Some muscle relaxers start working within 30 minutes of taking them, and the effects can last anywhere from 4 to 6 hours.

Addiction and Abuse

Muscle relaxants can be addictive for some people. Taking them without a prescription, or taking more than your doctor has recommended, can increase your chances of becoming addicted. So can using them over a long period of time.

Almost all cases of addiction and abuse are due to the drug carisoprodol (Soma), which is considered a schedule IV controlled substance. That’s because when the drug breaks down in your body, it produces a substance called meprobamate that acts like a tranquilizer. People who become addicted to carisoprodol sometimes abuse the drug because it makes them feel relaxed.

Other kinds of muscle relaxants may be addictive too. Cyclobenzaprine (Flexeril) has also been linked to misuse and abuse.

With prolonged use you can become physically dependent on some muscle relaxants. This means that without the medication, you can have withdrawl symptoms. You may have insomnia, vomiting or anxiety when you stop taking it.

Prescription medications

Prescription medications are divided into two groups: antispasmodics and antispastics. Antispasmodics are used to treat muscle spasms, and antispastics are used to treat muscle spasticity. Some antispasmodics, such as tizanidine, can be used to treat muscle spasticity. However, antispastics should not be used to treat muscle spasms.

Antispasmodics: Centrally acting skeletal muscle relaxants (SMRs)

Centrally acting SMRs are used in addition to rest and physical therapy to help relieve muscle spasms. They’re thought to work by causing a sedative effect or by preventing your nerves from sending pain signals to your brain.

You should only use these muscle relaxants for up to 2 or 3 weeks. The safety of longer-term use is not yet known.

While antispasmodics can be used to treat muscle spasms, they have not been shown to work better than nonsteroidal anti-inflammatory drugs (NSAIDs) or acetaminophen. In addition, they have more side effects than NSAIDs or acetaminophen.

The more common side effects of centrally acting SMRs include:

      • drowsiness
      • dizziness
      • headache
      • nervousness
      • reddish-purple or orange urine
      • lowered blood pressure upon standing

You should talk to your doctor about the benefits and risks of these medications for the treatment of your muscle spasms.

List of centrally acting SMRs

Generic name Brand name Form Generic available
carisoprodol Soma tablet yes
carisoprodol/aspirin not available tablet yes
carisoprodol/aspirin/codeine not available tablet yes
chlorzoxazone Parafon Forte, Lorzone tablet yes
cyclobenzaprine Fexmid, Flexeril, Amrix tablet, extended-release capsule tablet only
metaxalone Skelaxin, Metaxall tablet yes
methocarbamol Robaxin tablet yes
orphenadrine Norflex extended-release tablet yes
tizanidine Zanaflex tablet, capsule yes

Antispastics

Antispastics are used to treat muscle spasticity. They should not be used to treat muscle spasms. These drugs include:

Baclofen: Baclofen (Lioresal) is used to relieve spasticity caused by MS. It’s not fully understood how it works, but it seems to block nerve signals from the spinal cord that cause muscles to spasm. Side effects can include drowsiness, dizziness, weakness, and fatigue.

Dantrolene: Dantrolene (Dantrium) is used to treat muscle spasms caused by spinal cord injury, stroke, cerebral palsy, or MS. It works by acting directly on the skeletal muscle to relax the muscle spasm. Side effects can include drowsiness, dizziness, lightheadedness, and fatigue.

Diazepam: Diazepam (Valium) is used to relieve muscle spasms caused by inflammation, trauma, or muscle spasticity. It works by increasing the activity of a certain neurotransmitter to decrease the occurrence of muscle spasms. Diazepam is a sedative. Side effects can include drowsiness, fatigue, and muscle weakness.

List of antispastics

Generic name Brand name Form Generic available
baclofen Lioresal, Gablofen, Lioresal tablet, injection yes
dantrolene Dantrium tablet yes
diazepam Valium oral suspension, tablet, injection yes
Warnings for prescription muscle relaxants

Muscle relaxants such as carisoprodol and diazepam can be habit forming. Be sure to take your medication exactly as prescribed by your doctor.

Muscle relaxants can also cause withdrawal symptoms, such as seizures or hallucinations (sensing things that aren’t real). Do not suddenly stop taking your medication, especially if you’ve been taking it for a long time.

Also, muscle relaxants depress your central nervous system (CNS), making it hard to pay attention or stay awake. While taking a muscle relaxant, avoid activities that require mental alertness or coordination, such as driving or using heavy machinery.

You should not take muscle relaxants with:

  • alcohol
  • CNS depressant drugs, such as opioids or psychotropics
  • sleeping medications
  • herbal supplements such as St. John’s wort

Talk to your doctor about how you can safely use muscle relaxants if you:

  • are older than 65 years
  • have a mental health problem or brain disorder
  • have liver problems
Off-label medications for spasticity

Doctors can use certain medications to treat spasticity even when the drugs are not approved for that purpose by the U.S. Food and Drug Association (FDA). This is called off-label drug use. The following drugs are not actually muscle relaxants, but they can still help relieve symptoms of spasticity.

Benzodiazepines

Benzodiazepines are sedatives that can help relax muscles. They work by increasing the effects of certain neurotransmitters, which are chemicals that relay messages between your brain cells.

Examples of benzodiazepines include:

  • clonazepam (Klonopin)
  • lorazepam (Ativan)
  • alprazolam (Xanax)

Side effects of benzodiazepines can include drowsiness and problems with balance and memory. These drugs can also be habit forming.

Clonidine

Clonidine (Kapvay) is thought to work by preventing your nerves from sending pain signals to your brain or by causing a sedative effect.

Clonidine should not be used with other muscle relaxants. Taking it with similar drugs increases your risk of side effects. For instance, taking clonidine with tizanidine can cause very low blood pressure.

Clonidine is available in brand-name and generic versions.

Gabapentin

Gabapentin (Neurontin) is an anticonvulsant drug typically used to relieve seizures. It’s not fully known how gabapentin works to relieve muscle spasticity. Gabapentin is available in brand-name and generic versions.

Over-the-counter options for muscle spasms

OTC treatment is recommended as first-line therapy for muscle spasms caused by conditions such as acute lower back pain or tension headache. This means you should try OTC treatments before prescription medications.

OTC treatment options include nonsteroidal anti-inflammatory drugs (NSAIDs), acetaminophen, or a combination of both. Your doctor or pharmacist can help you choose an OTC treatment.

Nonsteroidal anti-inflammatory drugs (NSAIDs)

NSAIDs work by blocking your body from making certain substances that cause inflammation and pain. NSAIDs are available in generic and brand-name versions. They’re typically sold over the counter. Stronger versions are available by prescription.

NSAIDs come as oral tablets, capsules, or suspensions. They also come as chewable tablets for children. Side effects of these drugs can include upset stomach and dizziness.

Examples of NSAIDs include:

  • ibuprofen (Advil, Motrin)
  • naproxen (Aleve)

Acetaminophen

Acetaminophen (Tylenol) is thought to work by blocking your body from making certain substances that cause pain. Acetaminophen is available in generic and brand-name versions. It comes as immediate-release and extended release oral tablets and capsules, orally disintegrating tablets, chewable tablets, and oral solutions.

The more common side effects of acetaminophen can include nausea and upset stomach.

Cyclobenzaprine Medline Plus Drug Information

Why is this medication prescribed?

Cyclobenzaprine is used with rest, physical therapy, and other measures to relax muscles and relieve pain and discomfort caused by strains, sprains, and other muscle injuries. Cyclobenzaprine is in a class of medications called skeletal muscle relaxants. It works by acting in the brain and nervous system to allow the muscles to relax.

How should this medicine be used?

Cyclobenzaprine comes as a tablet and an extended-release capsule to take by mouth. The tablet is usually taken with or without food three times a day. The extended-release capsule is usually taken with or without food once a day. Do not take this drug for more than 3 weeks without talking to your doctor. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take cyclobenzaprine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the extended-release capsules whole; do not chew or crush them.

If you are not able to swallow the extended-release capsule whole, mix the contents of the capsule with applesauce. Eat the mixture right away and swallow without chewing. After you eat the mixture, take a drink, and swish and swallow to make sure that you have received all the medication.

Other uses for this medicine

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking cyclobenzaprine,

  • tell your doctor and pharmacist if you are allergic to cyclobenzaprine, any other medications, or any of the ingredients in cyclobenzaprine tablets or capsules. Ask your pharmacist for a list of the ingredients.
  • tell your doctor if you are taking the following medications or have stopped taking them within the past two weeks: monoamine oxidase (MAO) inhibitors, including isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam, Zelapar), and tranylcypromine (Parnate). Your doctor will probably tell you not to take cyclobenzaprine if you are taking one of these medications.
  • tell your doctor and pharmacist what other prescription and nonprescription drugs, vitamins, nutritional supplements and herbal products you are taking or plan to take. Be sure to mention any of the following: medications for allergies, coughs, or colds; barbiturates such as butabarbital (Butisol), phenobarbital, and secobarbital (Seconal); bupropion (Aplenzin, Forfivo XL, Wellbutrin, Zyban); meperidine (Demerol); sedatives; sleeping pills; selective serotonin reuptake inhibitors (SSRIs) such as citalopram (Celexa), escitalopram (Lexapro), fluoxetine (Prozac, Sarafem, Selfemra, in Symbyax), fluvoxamine (Luvox), paroxetine (Brisdelle, Paxil, Pexeva), and sertraline (Zoloft); selective serotonin and norepinephrine reuptake inhibitors (SNRIs) such as desvenlafaxine (Khedezla, Pristiq), duloxetine (Cymbalta), levomilnacipran (Fetzima), milnacipran (Savella) and venlafaxine (Effexor); tranquilizers; tricyclic antidepressants (TCAs) such as amitriptyline, amoxapine, clomipramine (Anafranil), desipramine (Norpramin), doxepin (Silenor), imipramine (Tofranil), nortriptyline (Pamelor), protriptyline (Vivactil), and trimipramine (Surmontil); tramadol (Conzip, Ultram, in Ultracet); verapamil (Calan, Covera HS, Verelan, in Tarka); or any other medication for depression, mood, anxiety, or thought disorder. Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Many other medications may also interact with cyclobenzaprine, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list. ;
  • tell your doctor if you are recovering from a recent heart attack, or if you have an overactive thyroid gland. heart failure (condition in which the heart is unable to pump enough blood to the other parts of the body), or an irregular heartbeat, heart block, or other problems with the electrical impulses of your heart. Your doctor will probably tell you not to take cyclobenzaprine.
  • tell your doctor if you have increased pressure in the eye or glaucoma, difficulty urinating, or liver disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while taking cyclobenzaprine, call your doctor immediately.
  • talk to your doctor about the risks and benefits of taking cyclobenzaprine if you are 65 years of age or older. Older adults should not usually take cyclobenzaprine because it is not as safe or effective as other medications that can be used to treat the same condition.
  • you should know that this drug may make you drowsy. Do not drive a car or operate machinery until you know how cyclobenzaprine affects you.
  • ask your doctor about the safe use of alcoholic beverages while you are taking cyclobenzaprine. Cyclobenzaprine can make the effects of alcohol worse.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for the missed one.

What side effects can this medication cause?

Cyclobenzaprine may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • dry mouth
  • dizziness
  • nausea
  • constipation
  • heartburn
  • extreme tiredness

If you experience any of the following symptoms, call your doctor immediately:

  • skin rash
  • hives
  • swelling of the face or tongue
  • difficulty breathing or swallowing
  • irregular or fast heart rate
  • chest pain

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration’s (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Store the extended-release capsule away from light.

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA’s Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can’t be awakened, immediately call emergency services at 911.

Symptoms of overdose may include the following:

  • drowsiness
  • fast or irregular heartbeat
  • feeling agitated
  • confusion
  • trouble speaking or moving
  • dizziness
  • nausea
  • vomiting
  • hallucination (seeing things or hearing voices that do not exist)
  • tremor
  • loss of consciousness

What other information should I know?

Keep all appointments with your doctor.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Amrix®
  • Flexeril®

This branded product is no longer on the market. Generic alternatives may be available.

Last Revised – 02/15/2017