- Side Effects
- Drug Interactions
- Pregnancy & Breastfeeding
- What Else to Know
Generic Name: metaxalone
Brand Name: Skelaxin
Drug Class: Skeletal Muscle Relaxants
What is metaxalone, and what is it used for?
Metaxalone is a medication that relaxes the skeletal muscles and is approved by the FDA for use as an adjunct to rest, physical therapy, and other measures to relieve discomfort from painful musculoskeletal conditions. Metaxalone is also used off-label to relieve pain from acute temporomandibular disorder.
While the precise way in which metaxalone works is not established, the muscle relaxation is believed to result from the central nervous system (CNS) depressant effects of the drug. Metaxalone has no direct effect on the skeletal muscles, it may disrupt the pain-spasm-pain cycle by generally depressing the central nervous system.
- Do not use in patients who:
- Are hypersensitive to metaxalone or any of its components
- Have a history of drug-induced anemias, including hemolytic anemia
- Have significant impairment of kidney or liver function.
- Metaxalone depresses the central nervous system, caution patients to avoid hazardous tasks that require physical and mental alertness.
- Metaxalone can enhance the effects of alcohol and other CNS depressants such as benzodiazepines, opioids, and tricyclic antidepressants.
- Elderly patients are more susceptible to CNS depression effects, so use with caution.
- Use metaxalone with great caution in patients with mild or moderate kidney or liver function impairment.
- Bioavailability of metaxalone may increase in women, so use with caution.
- Serotonin syndrome, a life-threatening drug reaction, may occur with concurrent use with serotonergic drugs including selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants, triptans, 5-HT3 receptor antagonists, monoamine oxidase inhibitors (MAOIs). Use with caution, monitor the patient for symptoms and discontinue metaxalone if serotonin syndrome is suspected.
What are the side effects of metaxalone?
Common side effects of metaxalone include:
- Gastrointestinal distress
- Drowsiness (somnolence)
Less common side effects of metaxalone include:
- Low red blood cell count due to rapid destruction (hemolytic anemia)
- Low leukocyte immune cell count (leukopenia)
- Immune hypersensitivity reaction
- Itching (pruritus)
Rare side effects of metaxalone include:
- Serious allergic reaction (anaphylaxis)
- Serotonin syndrome with higher doses or when used concurrently with serotonergic drugs
Call your doctor immediately if you experience any of the following symptoms or serious side effects while using this drug:
- Serious heart symptoms include fast or pounding heartbeats, fluttering in your chest, shortness of breath, and sudden dizziness;
- Severe headache, confusion, slurred speech, severe weakness, vomiting, loss of coordination, feeling unsteady;
- Severe nervous system reaction with very stiff muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, and feeling like you might pass out; or
- Serious eye symptoms include blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights.
This is not a complete list of all side effects or adverse reactions that may occur from the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may also report side effects or health problems to the FDA at 1-800-FDA-1088.
What are the dosages of metaxalone?
- 400 mg
- 800 mg
- Indicated for acute, painful musculoskeletal conditions
- 800 mg orally every 6-8 hours
- Mild to moderate impairment: Use caution
- Severe impairment: Contraindicated
- Mild to moderate impairment: Use caution
- Severe impairment: Contraindicated
- Children below 12 years: Safety and efficacy not established
- Children 12 years and above: 800 mg orally every 6-8 hours
- Metaxalone overdose can cause progressive sedation and hypnosis, and lead to respiratory failure and death.
- Treatment is supportive, including gastric lavage to eliminate undigested drug in the stomach.
- Kids With Autism Face Higher Odds of Vision Issues, But Many Don't Get Screened
- Mental Health Woes Double Women's Odds for Cervical Cancer
- Million-Person Study Finds Genes Common to Many Addiction Disorders
- Too Much Social Media Could Raise Risk for Eating Disorders
- Weaker Bones, Weakening Brain? Study Makes the Connection
- More Health News »
What drugs interact with metaxalone?
Inform your doctor of all medications you are currently taking, who can advise you on any possible drug interactions. Never begin taking, suddenly discontinue, or change the dosage of any medication without your doctor’s recommendation.
- Metaxalone has no listed severe interactions with other drugs.
- Serious interactions of metaxalone include:
- calcium/magnesium/potassium/sodium oxybates
- metoclopramide intranasal
- sodium oxybate
- sufentanil SL
- Metaxalone has moderate interactions with at least 174 different drugs.
- Mild Interactions of metaxalone include:
The drug interactions listed above are not all of the possible interactions or adverse effects. For more information on drug interactions, visit the RxList Drug Interaction Checker.
It is important to always tell your doctor, pharmacist, or healthcare provider about all prescription and over-the-counter medications you use, as well as the dosage for each, and keep a list of the information. Check with your doctor or healthcare provider if you have any questions about the medication.
Pregnancy and breastfeeding
- Animal reproductive studies have not shown evidence of fetal harm, however, there are no adequate and well-controlled studies in pregnant women. Metaxalone must be used only if benefits to the mother outweigh potential fetal risks.
- It is not known if metaxalone is present in breast milk, however, many drugs are excreted in breast milk. Discontinue nursing while on metaxalone therapy.
What else should I know about metaxalone?
- Take metaxalone exactly as prescribed.
- Avoid drinking alcohol and taking other CNS depressant drugs while on metaxalone therapy, they can have additive CNS depression effects.
- Metaxalone can impair physical and mental abilities, avoid hazardous activities such as driving and operating heavy machinery.
- Store safely out of reach of children.
- In case of overdose, seek immediate medical help or contact Poison Control.
Metaxalone is a medication that relaxes the skeletal muscles and is approved by the FDA for use as an adjunct to rest, physical therapy, and other measures to relieve discomfort from painful musculoskeletal conditions. Common side effects of metaxalone include nausea, vomiting, gastrointestinal distress, irritability, nervousness, headache, drowsiness (somnolence), dizziness, and others. Consult your doctor if pregnant or breastfeeding.
Multimedia: Slideshows, Images & Quizzes
Pain Management: Surprising Causes of Pain
What's causing your pain? Learn the common causes of lower back pain, as well as pain in the knee, stomach, kidney, shoulder,...
Pain Management: 15 Easy Ways to Reduce Chronic Pain
Chronic pain can be a symptom of many conditions, including arthritis, headaches, and others. Comprehensive chronic pain...
Muscle Cramps (Charley Horse) and Muscle Spasms
What are the differences between muscle spasms and cramps? Learn about the causes of muscle spasms and cramps (charley horse) in...
Pain Management: Signs Your Muscle Pain Is Something Else
Could your achy muscles be a sign of more than a tough workout? Learn when a twinge might warrant a visit to the doctor's office.
Pain Management: All About CBD Oil
Cannabidiol oil: It's made from marijuana and everyone seems to be talking about it. But what is it, and what does it really do?
Pain Management: One-Move Fixes for Pain and Stress
A quick stretch, yoga pose, or on-the-spot exercise can help fix sudden aches from head to toe. Learn how to quash pain with just...
Pain Management: Why Does My Calf Muscle Hurt?
There's a group of muscles on the back of each lower leg that doctors call "calf muscles." They play a key role in helping you...
Neck Pain: Causes of Stiffness, Muscle Spasms, Treatment, and Relief
What causes chronic neck pain? If you have poor posture, bad sleep habits, or spine problems, these issues can lead to a stiff...
Pain Management: Knee Pain Dos and Don'ts
Your knees go through a lot in the course of a day, and sometimes they can run into trouble. Here are a few things you can do...
Pain Management: Visual Guide to Frozen Shoulder
It's got nothing to do with cold weather. It means your shoulder is jammed up. WebMD guides you through the causes of frozen...
Arthritis: 16 Bad Habits That Cause Joint Pain
Being overweight, wearing uncomfortable shoes, or carrying a heavy purse can make joint pain and arthritis symptoms worse. Some...
Pain Management: All About Your Knees
They do their job so well that you might take them for granted. Learn how they're put together, what can go wrong with them, and...
Arthritis: Causes and Treatment for Joint Stiffness and Pain
Arthritis and injuries can leave your joints swollen, tender, and damaged. Discover treatments for morning stiffness, sore...
Pain Management: Why Knees Hurt
Your knees have lots of parts, and you use them a lot, so there's plenty that could go wrong. WebMD explains common things that...
10 Tips to Help You Sail Through Physical Therapy
Headed to physical therapy? WebMD shows you what to expect and how to get the most out of your sessions.
Pain Management: Ergonomic Tips for a Home Office
Are you working at home? Find out how to set up a workspace to prevent stiffness, protect your muscles and joints, and avoid...
Related Disease Conditions
Muscle spasms are involuntary muscle contractions that come on suddenly and are usually quite painful. Dehydration, doing strenuous exercise in a hot environment, prolonged muscle use, and certain diseases of the nervous system may cause muscle spasms. Symptoms and signs of a muscle spasm include an acute onset of pain and a possible bulge seen or felt beneath the skin where the muscle is located. Gently stretching the muscle usually resolves a muscle spasm.
What Is the Strongest Painkiller?
The most powerful pain reliever is a class of medications known as “opioids,” which have a significant risk of addiction and dependency. These drugs are routinely recommended by doctors for severe pain treatment, as well as a variety of other illnesses.
Pain Management and Rheumatoid Arthritis
Second Source article from WebMD
Pain management and treatment can be simple or complex, according to its cause. There are two basic types of pain, nociceptive pain and neuropathic pain. Some causes of neuropathic pain include: complex regional pain syndrome, interstitial cystitis, and irritable bowel syndrome. There are a variety of methods to treat chronic pain, which are dependant on the type of pain experienced.
What Foods Cause Joint Pain?
With arthritis, the constant pain and stiffness often lead the body to be in a state of stress or "inflammation." Foods that cause joint pain include heavily processed foods, red meat, foods high in sugar, fried foods, alcohol and foods rich in MSG, refined carbohydrates, gluten and purines.
What Do You Do When Pain Management Doesn't Work?
If you suffer from chronic pain, it can be frustrating when your pain medications are no longer effective. Here is what you can do when pain management doesn’t work.
Alternative Treatment (CAM) for MS
The term alternative therapy, in general, is used to describe any medical treatment or intervention that has not been scientifically documented or identified as safe or effective for a specific condition. Alternative therapy encompasses a variety of disciplines that range from diet and exercise to mental conditioning to lifestyle changes.
Is There a Difference Between Physiotherapy and Physical Therapy?
Physical therapy helps you recover faster from accident-related injuries and decreased joint movements due to joint conditions such as osteoarthritis and rheumatoid arthritis. There is no difference between physiotherapy and physical therapy. Both terms are used interchangeably all over the world.
Pain Management: Neuropathic Pain
Neuropathic pain is chronic pain resulting from injury to the nervous system. The injury can be to the central nervous system (brain and spinal cord) or the peripheral nervous system (nerves outside the brain and spinal cord).
What Is a Mild Pain Reliever?
Pain relievers ease discomfort caused by injury, illness, chronic health conditions, or surgery. Learn about mild vs. strong pain relievers and what to keep in mind when taking them.
Percutaneous Musculoskeletal Biopsy
Percutaneous needle technique musculoskeletal biopsy is a procedure to obtain a small piece of tissue (biopsy) from the muscles and/or the bones.
Treatment & Diagnosis
- Muscle Pain (Myalgia)
- Neuropathic Pain
- Pain Management
- Mind-Body-Pain Connection: How Does It Work?
- Cancer Pain Management with Ann Reiner
- Pain Management: Routes to Relief
- Acupuncture: Targeting Chronic Pain
- Pain: Managing the Pains and Aches of Office Life
- Pain Management: Painkiller Addiction
- Pain Awareness and Management
- Pain Management: Dealing with Back Pain
- Pain Management: OTC NSAIDs - Doctors Dialogue
- Pain Management Over-The-Counter
- Pain and Stress: Endorphins: Natural Pain and Stress Fighters
- Doctors Answer Pain Questions
- What Causes Rectal Muscle Spasms?
- What Pain Medication Can I Take While on Warfarin?
- Does Pain Medication Affect Men and Women Differently?
Medications & Supplements
Subscribe to MedicineNet's General Health Newsletter
Health Solutions From Our Sponsors
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.