Metaxalone is a skeletal muscle relaxant prescribed for short-term relief of pain and discomfort caused by acute musculoskeletal conditions, such as muscle strains, sprains, and spasms. It’s sold under the brand name Skelaxin and works by depressing activity in the central nervous system, which reduces the sensation of pain and muscle tightness. Metaxalone isn’t meant to be a standalone treatment. It’s approved specifically as an add-on to rest, physical therapy, and other measures.
Conditions Metaxalone Treats
Metaxalone is FDA-approved for acute, painful musculoskeletal conditions. In practice, that covers a range of common injuries and flare-ups: pulled muscles, back strains, neck stiffness from poor posture or injury, and painful muscle spasms. The key word is “acute,” meaning it’s designed for short-term use during a painful episode rather than for chronic pain management.
It’s approved for adults and for adolescents 13 years and older. Safety and effectiveness have not been established in children 12 and younger.
How Metaxalone Works
Metaxalone doesn’t act directly on your muscles. Instead, it works in the brain and spinal cord, dampening the nerve signals that create the sensation of pain and muscle tension. This central nervous system depression is what makes the drug effective, but it’s also why side effects like drowsiness can occur. The exact mechanism isn’t fully understood, but the net result is that your muscles feel less tight and the associated pain decreases.
Less Sedating Than Other Muscle Relaxants
One of the main reasons prescribers choose metaxalone over alternatives like cyclobenzaprine or tizanidine is its milder sedation profile. The American Academy of Family Physicians notes that metaxalone causes less dizziness and drowsiness than other skeletal muscle relaxants. If you’ve tried a muscle relaxant before and found it knocked you out, metaxalone may be a better fit for staying functional during the day. That said, it can still cause some drowsiness, so it’s worth seeing how you respond before driving or doing anything that requires sharp focus.
Common Side Effects
The most frequently reported side effects are nausea and vomiting, which occur in more than 5% of people taking the drug. Other common reactions include:
- Drowsiness and dizziness, though typically milder than with other muscle relaxants
- Headache
- Nervousness or irritability
- Gastrointestinal upset
Most of these side effects are mild and tend to resolve as your body adjusts or when you stop taking the medication.
Food Changes How Your Body Absorbs It
What you eat before taking metaxalone makes a significant difference in how much of the drug your body actually absorbs. In a clinical study of 59 healthy volunteers, taking metaxalone after a high-fat meal nearly tripled peak blood levels of the drug (a 194% increase) and increased total absorption by 142%, compared to taking it on an empty stomach. The time to reach peak levels also shifted from about 3 hours to nearly 5 hours.
This matters for two reasons. First, a fatty meal could amplify both the benefits and the side effects. Second, if you’re getting inconsistent results from the medication, your eating patterns around each dose could be why. Your prescriber may give you specific guidance on whether to take it with or without food.
Who Should Not Take Metaxalone
Metaxalone is not safe for everyone. It’s contraindicated in people with severely impaired kidney or liver function, since the drug is processed through those organs. It’s also off-limits for anyone with a known tendency toward drug-induced or hemolytic anemias, a condition where red blood cells break down faster than they should. And as with any medication, an allergy to any ingredient in the tablet rules it out.
Special Considerations for Older Adults
The recommended dose for people 65 and older is the same as for younger adults. However, clinical studies of metaxalone didn’t include enough older patients to determine whether they respond differently. Older adults may be especially susceptible to the central nervous system effects, meaning drowsiness and dizziness could be more pronounced and could increase fall risk. If you’re in this age group, starting cautiously and paying close attention to how you feel after the first few doses is a reasonable approach.
Interactions With Alcohol and Other Sedating Substances
Because metaxalone works by depressing central nervous system activity, combining it with other substances that do the same thing can stack those effects. Alcohol, sleep aids, anxiety medications, opioid painkillers, and antihistamines that cause drowsiness can all intensify sedation when taken alongside metaxalone. This combination can slow your breathing, impair coordination, and make you far more drowsy than either substance would alone.