Metaxalone 800mg Tablets
It is used to relax muscles.
Drug Class
Skeletal Muscle Relaxant
Pharmacologic Class
Centrally Acting Skeletal Muscle Relaxant
Pregnancy Category
Category C
FDA Approved
Aug 1962
DEA Schedule
Not Controlled
Overview
What is this medicine?
Metaxalone is a muscle relaxant used to help relieve pain and discomfort caused by muscle spasms. It works by affecting the brain and nervous system to help relax the muscles.
How to Use This Medicine
Taking Your Medication
To use this medication correctly, follow your doctor's instructions and read all the information provided. You can take this medication with or without food, but be aware that taking it with food may increase sleepiness or dizziness.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry place, avoiding the bathroom. Keep all medications in a safe location, out of the reach of children and pets. When disposing of unused or expired medications, do not flush them down the toilet or pour them down the drain unless instructed to do so. Instead, consult your pharmacist for guidance on the best disposal method or explore local drug take-back programs.
Missing a Dose
If you take this medication regularly, take a missed dose as soon as you remember. However, if it's close to the time for your next dose, skip the missed dose and resume your normal schedule. Do not take two doses at the same time or extra doses. If you take this medication as needed, do not take it more frequently than directed by your doctor.
To use this medication correctly, follow your doctor's instructions and read all the information provided. You can take this medication with or without food, but be aware that taking it with food may increase sleepiness or dizziness.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry place, avoiding the bathroom. Keep all medications in a safe location, out of the reach of children and pets. When disposing of unused or expired medications, do not flush them down the toilet or pour them down the drain unless instructed to do so. Instead, consult your pharmacist for guidance on the best disposal method or explore local drug take-back programs.
Missing a Dose
If you take this medication regularly, take a missed dose as soon as you remember. However, if it's close to the time for your next dose, skip the missed dose and resume your normal schedule. Do not take two doses at the same time or extra doses. If you take this medication as needed, do not take it more frequently than directed by your doctor.
Lifestyle & Tips
- Avoid alcohol and other medications that cause drowsiness (e.g., opioids, benzodiazepines, sedating antihistamines) as they can increase the sedative effects of metaxalone.
- Do not drive or operate heavy machinery until you know how this medication affects you, as it can cause drowsiness and dizziness.
- Take metaxalone with food if you experience stomach upset, as food can also increase its absorption.
- Do not stop taking this medication suddenly without consulting your doctor, especially if you have been taking it for a long time.
Available Forms & Alternatives
Available Strengths:
Dosing & Administration
Adult Dosing
Standard Dose:
800 mg three to four times daily
Dose Range:
2400 - 3200 mg
Condition-Specific Dosing:
acute painful musculoskeletal conditions:
800 mg three to four times daily
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established (Safety and effectiveness not established in patients under 12 years of age)
Adolescent:
Not established (Safety and effectiveness not established in patients under 12 years of age)
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment, use with caution
Moderate:
No specific adjustment, use with caution
Severe:
No specific adjustment, use with caution
Dialysis:
Not available (primarily metabolized by liver)
Hepatic Impairment:
Mild:
Use with caution, monitor LFTs
Moderate:
Contraindicated
Severe:
Contraindicated
Pharmacology
Mechanism of Action
The mechanism of action of metaxalone has not been established, but it is thought to be due to general central nervous system (CNS) depression rather than direct action on skeletal muscle.
Pharmacokinetics
Absorption:
Bioavailability:
Not precisely quantified, well absorbed
Tmax:
2-4 hours (fasted), 4-5 hours (fed)
FoodEffect:
Food significantly increases absorption (Cmax and AUC increase by 50-100%)
Distribution:
Vd:
Approximately 50 L/kg
ProteinBinding:
Approximately 90%
CnssPenetration:
Yes
Elimination:
HalfLife:
8-10 hours
Clearance:
Not available
ExcretionRoute:
Primarily renal as metabolites
Unchanged:
<1%
Pharmacodynamics
OnsetOfAction:
Approximately 1 hour
PeakEffect:
2-4 hours
DurationOfAction:
Approximately 4-6 hours
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Fever, chills, or sore throat
Severe stomach pain
Dark urine or yellow skin or eyes
Serotonin syndrome, a rare but life-threatening condition, which may occur with high doses of this medication or when taken with certain other drugs, such as those for depression, migraines, or other conditions. Symptoms of serotonin syndrome include:
+ Agitation
+ Change in balance
+ Confusion
+ Hallucinations
+ Fever
+ Fast or abnormal heartbeat
+ Flushing
+ Muscle twitching or stiffness
+ Seizures
+ Shivering or shaking
+ Excessive sweating
+ Severe diarrhea, upset stomach, or vomiting
+ Severe headache
Other Possible Side Effects
As with any medication, you may experience side effects. While many people have no side effects or only mild ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor:
Dizziness or drowsiness
Headache
Feeling nervous or excitable
Irritability
Upset stomach or vomiting
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Fever, chills, or sore throat
Severe stomach pain
Dark urine or yellow skin or eyes
Serotonin syndrome, a rare but life-threatening condition, which may occur with high doses of this medication or when taken with certain other drugs, such as those for depression, migraines, or other conditions. Symptoms of serotonin syndrome include:
+ Agitation
+ Change in balance
+ Confusion
+ Hallucinations
+ Fever
+ Fast or abnormal heartbeat
+ Flushing
+ Muscle twitching or stiffness
+ Seizures
+ Shivering or shaking
+ Excessive sweating
+ Severe diarrhea, upset stomach, or vomiting
+ Severe headache
Other Possible Side Effects
As with any medication, you may experience side effects. While many people have no side effects or only mild ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor:
Dizziness or drowsiness
Headache
Feeling nervous or excitable
Irritability
Upset stomach or vomiting
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe dizziness or extreme drowsiness
- Yellowing of the skin or eyes (jaundice)
- Dark urine
- Unusual tiredness or weakness (signs of liver problems)
- Signs of an allergic reaction such as rash, itching, swelling (especially of the face/tongue/throat), severe dizziness, or trouble breathing.
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you have a history of kidney disease or liver disease, as these conditions may affect how your body processes the medication.
* If you have anemia or have been informed that you are at risk of developing anemia, as this medication may impact your condition.
This list is not exhaustive, and it is crucial to discuss all your medications, including prescription and over-the-counter drugs, natural products, and vitamins, with your doctor and pharmacist. They will help you determine if it is safe to take this medication in conjunction with your other medications and health conditions.
To ensure your safety, do not start, stop, or change the dosage of any medication without first consulting your doctor. It is vital to verify that all your medications and health conditions are compatible with this medication to minimize potential interactions and adverse effects.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you have a history of kidney disease or liver disease, as these conditions may affect how your body processes the medication.
* If you have anemia or have been informed that you are at risk of developing anemia, as this medication may impact your condition.
This list is not exhaustive, and it is crucial to discuss all your medications, including prescription and over-the-counter drugs, natural products, and vitamins, with your doctor and pharmacist. They will help you determine if it is safe to take this medication in conjunction with your other medications and health conditions.
To ensure your safety, do not start, stop, or change the dosage of any medication without first consulting your doctor. It is vital to verify that all your medications and health conditions are compatible with this medication to minimize potential interactions and adverse effects.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. Adhere strictly to the dosage prescribed by your doctor, as taking more than the recommended amount can increase your risk of experiencing severe side effects.
Until you are familiar with how this medication affects you, avoid operating a vehicle or engaging in any activities that require your full attention. Before consuming alcohol, using marijuana or other cannabis products, or taking any prescription or over-the-counter medications that may cause drowsiness, consult with your doctor.
This medication is typically used in conjunction with rest, physical therapy, pain management medications, and other therapeutic interventions. It may influence the results of certain laboratory tests, so it is crucial that your doctor and laboratory personnel are aware that you are taking this drug.
If you are 65 years of age or older, exercise caution when using this medication, as you may be more susceptible to side effects. If you are pregnant, planning to become pregnant, or are breastfeeding, discuss the potential benefits and risks of this medication with your doctor to ensure the well-being of both you and your baby.
Until you are familiar with how this medication affects you, avoid operating a vehicle or engaging in any activities that require your full attention. Before consuming alcohol, using marijuana or other cannabis products, or taking any prescription or over-the-counter medications that may cause drowsiness, consult with your doctor.
This medication is typically used in conjunction with rest, physical therapy, pain management medications, and other therapeutic interventions. It may influence the results of certain laboratory tests, so it is crucial that your doctor and laboratory personnel are aware that you are taking this drug.
If you are 65 years of age or older, exercise caution when using this medication, as you may be more susceptible to side effects. If you are pregnant, planning to become pregnant, or are breastfeeding, discuss the potential benefits and risks of this medication with your doctor to ensure the well-being of both you and your baby.
Overdose Information
Overdose Symptoms:
- Severe drowsiness
- Dizziness
- Nausea
- Vomiting
- Loss of coordination (ataxia)
- Respiratory depression
- Coma
What to Do:
Seek immediate medical attention or call Poison Control at 1-800-222-1222. Treatment is generally supportive, including gastric lavage, activated charcoal, and maintenance of vital signs.
Drug Interactions
Major Interactions
Moderate Interactions
- Sedative hypnotics
- Antipsychotics
Monitoring
Baseline Monitoring
Liver Function Tests (ALT, AST, Bilirubin)
Rationale: Metaxalone is metabolized by the liver and is contraindicated in patients with known or suspected hepatic impairment. Baseline assessment is crucial.
Timing: Prior to initiation of therapy
Renal Function (BUN, Creatinine)
Rationale: General assessment of organ function, though renal excretion is primarily of metabolites.
Timing: Prior to initiation of therapy
Routine Monitoring
Therapeutic effect (reduction in muscle spasm and pain)
Frequency: Daily/as needed
Target: Improved comfort and mobility
Action Threshold: Lack of efficacy may require dose adjustment or alternative therapy
Adverse effects (drowsiness, dizziness, GI upset)
Frequency: Daily/as needed
Target: Minimal to tolerable side effects
Action Threshold: Severe or intolerable side effects may require dose reduction or discontinuation
Symptom Monitoring
- Drowsiness
- Dizziness
- Nausea
- Vomiting
- Stomach upset
- Headache
- Nervousness
- Irritability
- Rash
- Jaundice (yellowing of skin/eyes)
- Dark urine
- Unusual tiredness (signs of liver problems)
- Signs of allergic reaction (e.g., rash, itching, swelling, severe dizziness, trouble breathing)
Special Patient Groups
Pregnancy
Pregnancy Category C. There are no adequate and well-controlled studies in pregnant women. Metaxalone should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
Trimester-Specific Risks:
First Trimester:
Potential risk, but human data is lacking. Use only if clearly needed.
Second Trimester:
Potential risk, but human data is lacking. Use only if clearly needed.
Third Trimester:
Potential risk, but human data is lacking. Use only if clearly needed.
Lactation
It is not known whether metaxalone is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when metaxalone is administered to a nursing woman. Monitor infant for sedation.
Infant Risk:
Potential for CNS depression in the infant. Use with caution.
Pediatric Use
Safety and effectiveness have not been established in pediatric patients under 12 years of age. Use is generally not recommended.
Geriatric Use
Use with caution in elderly patients due to increased sensitivity to CNS depressant effects. Consider starting with lower doses and titrating slowly.
Clinical Information
Clinical Pearls
- Metaxalone is generally considered to be one of the less sedating muscle relaxants, but patients should still be cautioned about potential drowsiness and dizziness.
- Taking metaxalone with food can significantly increase its absorption and may help reduce gastrointestinal upset.
- It is contraindicated in patients with significant hepatic impairment due to its extensive liver metabolism.
- Patients should be strongly advised to avoid alcohol and other CNS depressants while taking metaxalone due to the risk of additive sedative effects.
Alternative Therapies
- Cyclobenzaprine
- Tizanidine
- Baclofen
- Carisoprodol
- Methocarbamol
- Orphenadrine
- Physical therapy
- Heat/cold therapy
- NSAIDs (for pain management)
Cost & Coverage
Average Cost:
$30 - $100 per 30 tablets (generic 800mg)
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 2 (for generic)
General Drug Facts
If your symptoms or health issues persist or worsen, it is essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so it's a good idea to check with your pharmacist. If you have any questions or concerns about this medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek medical attention. When seeking help, be prepared to provide detailed information about the overdose, including the medication taken, the amount, and the time it occurred.