Metaxalone

About Metaxalone

The label says metaxalone’s mechanism has not been fully characterized but may be related to its sedative properties. It is labeled as an adjunct to rest, physical therapy and other measures for the discomfort of acute, painful musculoskeletal conditions in adults and children 13 and older; safety and effectiveness at 12 and younger have not been established. The dose is 800 mg three to four times a day, and adults 65 and older take the same dose as younger adults. A 640 mg metaxalone tablet is a separate product that is not substituted milligram for milligram with the 800 mg tablet: the label allows a switch from 640 mg to 800 mg only in people who have been taking it on an empty stomach.

There is no boxed warning. Serotonin syndrome, which can be life-threatening, has been reported when metaxalone at usual doses was taken with other serotonergic drugs and when metaxalone alone was taken above the recommended dose; symptoms include agitation, hallucinations, a fast heartbeat, fever, stiffness, poor coordination, nausea, vomiting and diarrhea, and it is stopped if serotonin syndrome is suspected. It depresses the central nervous system and can impair driving and other hazardous tasks, especially with alcohol or other sedatives, and older adults may be especially sensitive. It must not be taken by anyone allergic to it, with a known tendency to drug-induced, hemolytic or other anemias, or with severe kidney or liver impairment; with mild to moderate impairment it is used with caution and closer follow-up. Nausea and vomiting are the most common side effects; drowsiness, dizziness, headache and irritability are also reported.

A high-fat meal increases how much metaxalone is absorbed, and the Skelaxin label adds that taking it with food may increase drowsiness, to which older adults may be especially susceptible. Deaths from overdose have occurred, particularly with alcohol or other sedatives. Metaxalone can cause a false-positive Benedict’s test for sugar in the urine, which a glucose-specific test tells apart. There are no data on its use in pregnancy or on whether it passes into breast milk, so plans for either are worth discussing with the prescriber.

Taking Metaxalone

How to take it

Usually three or four times a day as prescribed, alongside rest and physical therapy. Take it the same way each time, either always with food or always without, because a high-fat meal increases how much is absorbed and food may add to drowsiness. Avoid driving or hazardous work until you know how it affects you.

If you miss a dose

Take it as soon as you can, unless it is almost time for the next dose; then skip the missed dose. Do not take two doses at once.

Storage

At room temperature, away from moisture and heat, and out of the reach of children.

Interactions to know about

SSRI and SNRI antidepressants, tricyclic antidepressants, triptans, MAO inhibitors (including linezolid and intravenous methylene blue) and opioids, particularly fentanyl, meperidine and methadone, can cause serotonin syndrome with it. Alcohol, benzodiazepines, opioids and other sedatives add to drowsiness. It can also cause a false-positive Benedict’s test for urine sugar.

This summarizes the official prescribing information. Your prescriber’s and pharmacist’s instructions, and the leaflet that comes with your medicine, take priority.

Why the cash price for Metaxalone differs from pharmacy to pharmacy

With the Skelaxin brand listed as discontinued, prescriptions are filled with generics, and quotes for the 800 mg tablet differ mainly by the pharmacy’s fee and markup and whether metaxalone is on its flat-price generic list. Three or four tablets a day add up where a pharmacy prices per tablet.

Other strengths are priced on their own. A dose written as two 400 mg tablets means twice as many tablets, and because the 640 mg and 800 mg tablets are not substituted for each other, a pharmacy that does not stock the strength written may need to order it or ask the prescriber for a new prescription.

Ways to pay less for Metaxalone without insurance

• Ask whether metaxalone is on the pharmacy’s flat-price generic list, and compare more than one pharmacy.
• If your prescription is for two 400 mg tablets per dose, ask the prescriber whether one 800 mg tablet would suit you.
• Ask the prescriber how many days you need it, so the quantity matches a short course.
• If it is quoted high, ask the prescriber whether another generic muscle relaxant, such as methocarbamol, would suit you.
• Upload the prescription to Script Unlock so licensed pharmacies can quote their cash price. You pay the pharmacy directly.

Questions to ask your pharmacist about Metaxalone

1. 1.Should I take it with food or on an empty stomach, and does it matter which?
2. 2.Is it safe with my antidepressant, migraine medicine or pain medicine?
3. 3.Which symptoms of serotonin syndrome mean I should stop it and get help?
4. 4.Can I drive or drink alcohol while I take it?

Related medications