A muscle relaxant for short-term muscle spasm
Metaxalone
A muscle relaxant used for the short-term relief of muscle spasm, alongside rest and physiotherapy.
What is Metaxalone?
Metaxalone is a muscle relaxant used for the short-term relief of painful muscle spasm, usually together with rest and physiotherapy rather than on its own. It is taken by mouth. Its main side effect is drowsiness, so it can affect driving and is used with care alongside alcohol and other sedating medicines. It is used cautiously in people with liver or kidney problems, who may need monitoring. It is largely a United States product and is not in common use in the UK, so a UK prescriber may suggest more familiar alternatives.
Education and reference only. This is a plain-language guide to Metaxalone — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Metaxalone is a muscle relaxant used to ease painful muscle spasm, typically from a strain or other short-term muscle problem. It is meant for short-term use as part of a wider approach that includes rest, physiotherapy and other pain relief, rather than as a long-term treatment on its own. It is taken by mouth as a tablet. It is largely a product of the United States and is not commonly prescribed in the UK, where other muscle relaxants and approaches are more usual, so a UK prescriber may recommend a more familiar option.
How it works
Metaxalone is thought to work mainly by having a general calming effect on the nervous system rather than acting directly on the muscle itself. By dampening down the nerve signals involved, it can reduce the painful tightening of muscles in spasm. Because its effect comes partly from this sedating action, drowsiness is its most common side effect. It is intended to work alongside rest and physiotherapy during the short period when a muscle problem is at its worst, rather than as a long-term treatment.
Company & origin
Originated / developed by: Generic.
A muscle relaxant used mainly in the United States for short-term muscle spasm; it is not commonly used in the UK.
Practical use
How to take Metaxalone
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take it by mouth as prescribed, for the short period advised rather than long term.
- Use it alongside rest and physiotherapy, as it works best as part of a wider plan.
- Take care with driving and machinery, as it can make you drowsy.
- Avoid or limit alcohol and other sedating medicines, which add to drowsiness.
- Tell your prescriber about any liver or kidney problems before starting.
Weighing it up
Advantages & disadvantages of Metaxalone
Advantages
- Can ease painful muscle spasm in the short term.
- Taken by mouth as part of a wider plan with rest and physiotherapy.
- Generally intended for brief use rather than long-term treatment.
Disadvantages
- Commonly causes drowsiness, which can affect driving and daily activities.
- Used with caution in people with liver or kidney problems, who may need monitoring.
- Largely a United States product and not in common UK use, so alternatives are often preferred here.
Practical use
Good to know
The most useful thing to know about metaxalone is that it is for short-term relief of muscle spasm and works best as part of a wider plan with rest and physiotherapy, not as a standalone or long-term treatment. Its main side effect is drowsiness, so it can affect your ability to drive or operate machinery, and combining it with alcohol or other sedating medicines can make this much worse. It is used cautiously in people with liver or kidney problems, who may need monitoring, because the body has to process and clear the medicine. It is largely a United States product and is not in common UK use, so a UK prescriber may well suggest a more familiar muscle relaxant or approach. Tell your prescriber about all your medicines and any liver or kidney problems.
Who should not take it / use with caution
- People who have had a serious allergic reaction to metaxalone should not take it.
- It is used with caution, or avoided, in people with significant liver or kidney problems.
- It is used with care in older people and in anyone who needs to drive or operate machinery, because of drowsiness.
Monitoring
- Reviewing how well the muscle spasm and pain settle over the short course.
- Watching for drowsiness and its effect on daily activities.
- Checking liver function where there is concern, particularly with liver problems.
Side effects
- Drowsiness, dizziness or headache.
- Nausea or stomach upset.
- Rarely, allergic reactions or changes in liver blood tests.
Key interactions
- Alcohol and other sedating medicines add to drowsiness, so they are best avoided or limited.
- It may add to the effects of other medicines that affect the nervous system.
- Tell your prescriber about all your medicines, including those bought over the counter.
Available as: Tablets taken by mouth.
Answers
Metaxalone: frequently asked questions
What is metaxalone used for?
It is a muscle relaxant used for the short-term relief of painful muscle spasm, usually alongside rest and physiotherapy rather than on its own.
Will it make me drowsy?
Drowsiness is its most common side effect, so take care with driving and machinery and be cautious with alcohol and other sedating medicines.
Is it used in the UK?
It is largely a United States product and is not in common UK use, so a UK prescriber may suggest a more familiar muscle relaxant or approach.
Can I take it long term?
No, it is intended for short-term use during the worst of a muscle problem, as part of a wider plan with rest and physiotherapy.
Is it safe with liver or kidney problems?
It is used with caution in people with liver or kidney problems, who may need monitoring, so tell your prescriber about these before starting.
The wider class
About Muscle relaxant (skeletal muscle)
Metaxalone belongs to the muscle relaxant (skeletal muscle) class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF
- NICE CKS
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