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What are metaxalone 800 mg: Metaxalone: MedlinePlus Drug Information

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Metaxalone – an overview | ScienceDirect Topics

Muscle Relaxants

Muscle relaxants decrease muscle tone and are used to relieve symptoms such as muscle spasms, cramping, hyperreflexia, tension headaches, neck pain, lower back pain, fibromyalgia, and myofascial pain syndrome. There are two main groups of muscle relaxants: neuromuscular blockers which have no CNS activity, and spasmolytics which are almost all centrally acting. Examples of commonly prescribed spasmolytics include carisoprodol (e.g., Soma® and Sanoma®), cyclobenzaprine (e.g., Flexeril® and Amrix®), metaxalone (e.g., Skelaxin®), methocarbamol (e.g., Robaxin®), tizanidine (e.g., Zanaflex®), baclofen (e.g., Lioresal® and Liofen®), and dantrolene (e.g., Dantrium®). Dantrolene is a peripherally acting muscle relaxant with no CNS activity. Off-label use of the anticonvulsant drug gabapentin (e.g., Neurontin®) includes the treatment of restless leg syndrome and the lessening of pain and spasticity in multiple sclerosis.

Carisoprodol is a centrally acting skeletal muscle relaxant commonly prescribed for the treatment of acute musculoskeletal pain. It is available in tablet form either on its own or in combination with aspirin or codeine. Meprobamate is the primary metabolite of carisoprodol; however, it is also a CNS depressant in its own right (Miltown® and Equanil®) and is indicated for the management of anxiety disorders and for short-term treatment of anxiety symptoms. Both carisoprodol and meprobamate are frequently prescribed with other drugs such as opiates and benzodiazepines to control chronic pain.

Following therapeutic use, the effects of carisoprodol begin within 30 min and last for up to 4–6 h. Meprobamate has a much longer duration of effect and drug accumulation may occur during chronic therapy. Unwanted effects are common with both drugs and include dizziness, drowsiness, disorientation, unsteadiness, slurred speech, ataxia, and tremor. Patients also have a tendency to doze off or fall asleep. In higher doses, patients may experience intoxication or drunken behavior, loss of balance and coordination, weakness, agitation, disorientation to place and time, and sleep disturbances. In abuse or overdose, patients may be consistently sedated and even become comatose. Overdose symptoms can include shallow breathing, clammy skin, weak and rapid pulse, paradoxical insomnia, convulsions, severe respiratory depression, and possibly death.

Following chronic use of either drug, development of abuse and moderate physical and psychological dependence can occur. Abrupt discontinuation after long-term use can result in mild withdrawal symptoms such as anxiety, abdominal cramps, insomnia, vomiting, muscle twitching, confusion, and occasionally chills, convulsions, and hallucinations.

Skelaxin (metaxalone) dosing, indications, interactions, adverse effects, and more

  • abametapir

    Serious – Use Alternative (1)abametapir will increase the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. For 2 weeks after abametapir application, avoid taking drugs that are CYP3A4 substrates. If not feasible, avoid use of abametapir.

  • abiraterone

    Monitor Closely (1)abiraterone increases levels of metaxalone by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Avoid coadministration of abiraterone with substrates of CYP2D6. If alternative therapy cannot be used, exercise caution and consider a dose reduction of the CYP2D6 substrate.

  • abobotulinumtoxinA

    Monitor Closely (1)metaxalone increases effects of abobotulinumtoxinA by pharmacodynamic synergism. Use Caution/Monitor. Muscle relaxants may enhance botulinum toxin effects. Closely monitor for increased neuromuscular blockade.

  • alfentanil

    Monitor Closely (1)metaxalone and alfentanil both increase sedation. Use Caution/Monitor.

  • alprazolam

    Monitor Closely (1)alprazolam and metaxalone both increase sedation. Use Caution/Monitor.

  • amitriptyline

    Monitor Closely (1)metaxalone and amitriptyline both increase sedation. Use Caution/Monitor.

  • amobarbital

    Monitor Closely (2)amobarbital will decrease the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

    amobarbital and metaxalone both increase sedation. Use Caution/Monitor.

  • amoxapine

    Monitor Closely (1)metaxalone and amoxapine both increase sedation. Use Caution/Monitor.

  • apalutamide

    Serious – Use Alternative (1)apalutamide will decrease the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of apalutamide, a strong CYP3A4 inducer, with drugs that are CYP3A4 substrates can result in lower exposure to these medications. Avoid or substitute another drug for these medications when possible. Evaluate for loss of therapeutic effect if medication must be coadministered. Adjust dose according to prescribing information if needed.

  • apomorphine

    Monitor Closely (1)metaxalone and apomorphine both increase sedation. Use Caution/Monitor.

  • aripiprazole

    Monitor Closely (1)metaxalone and aripiprazole both increase sedation. Use Caution/Monitor.

  • azelastine

    Monitor Closely (1)azelastine and metaxalone both increase sedation. Use Caution/Monitor.

  • baclofen

    Monitor Closely (1)baclofen and metaxalone both increase sedation. Use Caution/Monitor.

  • belladonna and opium

    Monitor Closely (1)metaxalone and belladonna and opium both increase sedation. Use Caution/Monitor.

  • benperidol

    Monitor Closely (1)metaxalone and benperidol both increase sedation. Use Caution/Monitor.

  • benzhydrocodone/acetaminophen

    Serious – Use Alternative (1)benzhydrocodone/acetaminophen, metaxalone.
    Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

  • benzphetamine

    Monitor Closely (1)metaxalone increases and benzphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

  • brexanolone

    Monitor Closely (1)brexanolone, metaxalone.
    Either increases toxicity of the other by sedation. Use Caution/Monitor.

  • brompheniramine

    Monitor Closely (1)brompheniramine and metaxalone both increase sedation. Use Caution/Monitor.

  • buprenorphine

    Monitor Closely (1)metaxalone and buprenorphine both increase sedation. Use Caution/Monitor.

  • buprenorphine buccal

    Monitor Closely (1)metaxalone and buprenorphine buccal both increase sedation. Use Caution/Monitor.

  • buprenorphine, long-acting injection

    Monitor Closely (1)buprenorphine, long-acting injection increases effects of metaxalone by Other (see comment). Modify Therapy/Monitor Closely.
    Comment: Buprenorphine may enhance the neuromuscular blocking action of skeletal muscle relaxants and increase risk for respiratory depression. Monitor for signs of respiratory depression that may be greater than otherwise expected and decrease muscle relaxant dosage as necessary.

  • butabarbital

    Monitor Closely (1)butabarbital and metaxalone both increase sedation. Use Caution/Monitor.

  • butalbital

    Monitor Closely (1)butalbital and metaxalone both increase sedation. Use Caution/Monitor.

  • butorphanol

    Monitor Closely (1)metaxalone and butorphanol both increase sedation. Use Caution/Monitor.

  • calcium/magnesium/potassium/sodium oxybates

    Serious – Use Alternative (1)metaxalone, calcium/magnesium/potassium/sodium oxybates.
    Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

  • cannabidiol

    Monitor Closely (1)cannabidiol, metaxalone. affecting hepatic enzyme CYP1A2 metabolism. Modify Therapy/Monitor Closely. Owing to the potential for both CYP1A2 induction and inhibition with the coadministration of CYP1A2 substrates and cannabidiol, consider reducing dosage adjustment of CYP1A2 substrates as clinically appropriate.

  • carbinoxamine

    Monitor Closely (1)carbinoxamine and metaxalone both increase sedation. Use Caution/Monitor.

  • carisoprodol

    Monitor Closely (1)carisoprodol and metaxalone both increase sedation. Use Caution/Monitor.

  • cenobamate

    Monitor Closely (1)cenobamate will decrease the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Increase dose of CYP3A4 substrate, as needed, when coadministered with cenobamate.

  • chloral hydrate

    Monitor Closely (1)chloral hydrate and metaxalone both increase sedation. Use Caution/Monitor.

  • chlordiazepoxide

    Monitor Closely (1)chlordiazepoxide and metaxalone both increase sedation. Use Caution/Monitor.

  • chlorpheniramine

    Monitor Closely (1)chlorpheniramine and metaxalone both increase sedation. Use Caution/Monitor.

  • chlorpromazine

    Monitor Closely (1)metaxalone and chlorpromazine both increase sedation. Use Caution/Monitor.

  • chlorzoxazone

    Monitor Closely (1)chlorzoxazone and metaxalone both increase sedation. Use Caution/Monitor.

  • cinnarizine

    Monitor Closely (1)cinnarizine and metaxalone both increase sedation. Use Caution/Monitor.

  • clemastine

    Monitor Closely (1)clemastine and metaxalone both increase sedation. Use Caution/Monitor.

  • clobazam

    Monitor Closely (1)metaxalone, clobazam. Other (see comment). Use Caution/Monitor.
    Comment: Concomitant administration can increase the potential for CNS effects (e.g., increased sedation or respiratory depression).

  • clomipramine

    Monitor Closely (1)metaxalone and clomipramine both increase sedation. Use Caution/Monitor.

  • clonazepam

    Monitor Closely (1)clonazepam and metaxalone both increase sedation. Use Caution/Monitor.

  • clorazepate

    Monitor Closely (1)clorazepate and metaxalone both increase sedation. Use Caution/Monitor.

  • clozapine

    Monitor Closely (1)metaxalone and clozapine both increase sedation. Use Caution/Monitor.

  • codeine

    Monitor Closely (1)metaxalone and codeine both increase sedation. Use Caution/Monitor.

  • crofelemer

    Monitor Closely (1)crofelemer increases levels of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Crofelemer has the potential to inhibit CYP3A4 at concentrations expected in the gut; unlikely to inhibit systemically because minimally absorbed.

  • cyclizine

    Monitor Closely (1)cyclizine and metaxalone both increase sedation. Use Caution/Monitor.

  • cyclobenzaprine

    Monitor Closely (1)cyclobenzaprine and metaxalone both increase sedation. Use Caution/Monitor.

  • cyproheptadine

    Monitor Closely (1)cyproheptadine and metaxalone both increase sedation. Use Caution/Monitor.

  • dabrafenib

    Monitor Closely (1)dabrafenib will decrease the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.

  • dantrolene

    Monitor Closely (1)dantrolene and metaxalone both increase sedation. Use Caution/Monitor.

  • desipramine

    Monitor Closely (1)metaxalone and desipramine both increase sedation. Use Caution/Monitor.

  • dexchlorpheniramine

    Monitor Closely (1)dexchlorpheniramine and metaxalone both increase sedation. Use Caution/Monitor.

  • dexfenfluramine

    Monitor Closely (1)metaxalone increases and dexfenfluramine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

  • dexmedetomidine

    Monitor Closely (1)dexmedetomidine and metaxalone both increase sedation. Use Caution/Monitor.

  • dextromoramide

    Monitor Closely (1)metaxalone and dextromoramide both increase sedation. Use Caution/Monitor.

  • diamorphine

    Monitor Closely (1)metaxalone and diamorphine both increase sedation. Use Caution/Monitor.

  • diazepam

    Monitor Closely (1)diazepam and metaxalone both increase sedation. Use Caution/Monitor.

  • diazepam intranasal

    Monitor Closely (1)diazepam intranasal, metaxalone.
    Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Coadministration may potentiate the CNS-depressant effects of each drug.

  • difenoxin hcl

    Monitor Closely (1)metaxalone and difenoxin hcl both increase sedation. Use Caution/Monitor.

  • dimenhydrinate

    Monitor Closely (1)dimenhydrinate and metaxalone both increase sedation. Use Caution/Monitor.

  • diphenhydramine

    Monitor Closely (1)diphenhydramine and metaxalone both increase sedation. Use Caution/Monitor.

  • diphenoxylate hcl

    Monitor Closely (1)metaxalone and diphenoxylate hcl both increase sedation. Use Caution/Monitor.

  • dipipanone

    Monitor Closely (1)metaxalone and dipipanone both increase sedation. Use Caution/Monitor.

  • dopexamine

    Monitor Closely (1)metaxalone increases and dopexamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

  • dosulepin

    Monitor Closely (1)metaxalone and dosulepin both increase sedation. Use Caution/Monitor.

  • doxepin

    Monitor Closely (1)metaxalone and doxepin both increase sedation. Use Caution/Monitor.

  • doxylamine

    Monitor Closely (1)doxylamine and metaxalone both increase sedation. Use Caution/Monitor.

  • droperidol

    Monitor Closely (1)metaxalone and droperidol both increase sedation. Use Caution/Monitor.

  • efavirenz

    Monitor Closely (1)efavirenz will decrease the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

  • elagolix

    Monitor Closely (1)elagolix decreases levels of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.

  • elvitegravir/cobicistat/emtricitabine/tenofovir DF

    Monitor Closely (2)elvitegravir/cobicistat/emtricitabine/tenofovir DF increases levels of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Cobicistat is a CYP3A4 inhibitor; contraindicated with CYP3A4 substrates for which elevated plasma concentrations are associated with serious and/or life-threatening events.

    elvitegravir/cobicistat/emtricitabine/tenofovir DF increases levels of metaxalone by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. Cobicistat is a CYP2D6 inhibitor; caution with CYP2D6 substrates for which elevated plasma concentrations are associated with serious and/or life-threatening events.

  • encorafenib

    Monitor Closely (1)encorafenib, metaxalone. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Encorafenib both inhibits and induces CYP3A4 at clinically relevant plasma concentrations. Coadministration of encorafenib with sensitive CYP3A4 substrates may result in increased toxicity or decreased efficacy of these agents.

  • esketamine intranasal

    Monitor Closely (1)esketamine intranasal, metaxalone.
    Either increases toxicity of the other by sedation. Modify Therapy/Monitor Closely.

  • estazolam

    Monitor Closely (1)estazolam and metaxalone both increase sedation. Use Caution/Monitor.

  • ethanol

    Monitor Closely (1)metaxalone and ethanol both increase sedation. Use Caution/Monitor.

  • etomidate

    Monitor Closely (1)etomidate and metaxalone both increase sedation. Use Caution/Monitor.

  • eucalyptus

    Minor (1)metaxalone and eucalyptus both increase sedation. Minor/Significance Unknown.

  • fedratinib

    Monitor Closely (1)fedratinib will increase the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Adjust dose of drugs that are CYP3A4 substrates as necessary.

  • fenfluramine

    Monitor Closely (1)metaxalone increases and fenfluramine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

  • fexinidazole

    Serious – Use Alternative (1)fexinidazole will increase the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Fexinidazole inhibits CYP3A4. Coadministration may increase risk for adverse effects of CYP3A4 substrates.

  • fluphenazine

    Monitor Closely (1)metaxalone and fluphenazine both increase sedation. Use Caution/Monitor.

  • flurazepam

    Monitor Closely (1)flurazepam and metaxalone both increase sedation. Use Caution/Monitor.

  • haloperidol

    Monitor Closely (1)metaxalone and haloperidol both increase sedation. Use Caution/Monitor.

  • hydrocodone

    Serious – Use Alternative (1)hydrocodone, metaxalone.
    Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

  • hydromorphone

    Monitor Closely (1)metaxalone and hydromorphone both increase sedation. Use Caution/Monitor.

  • hydroxyzine

    Monitor Closely (1)hydroxyzine and metaxalone both increase sedation. Use Caution/Monitor.

  • idelalisib

    Serious – Use Alternative (1)idelalisib will increase the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Idelalisib is a strong CYP3A inhibitor; avoid coadministration with sensitive CYP3A substrates

  • iloperidone

    Monitor Closely (2)metaxalone and iloperidone both increase sedation. Use Caution/Monitor.

    iloperidone increases levels of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Iloperidone is a time-dependent CYP3A inhibitor and may lead to increased plasma levels of drugs predominantly eliminated by CYP3A4.

  • imipramine

    Monitor Closely (1)metaxalone and imipramine both increase sedation. Use Caution/Monitor.

  • incobotulinumtoxinA

    Monitor Closely (1)metaxalone, incobotulinumtoxinA.
    Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Muscle relaxants may enhance botulinum toxin effects. Closely monitor for increased neuromuscular blockade.

  • istradefylline

    Monitor Closely (1)istradefylline will increase the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Istradefylline 40 mg/day increased peak levels and AUC of CYP3A4 substrates in clinical trials. This effect was not observed with istradefylline 20 mg/day. Consider dose reduction of sensitive CYP3A4 substrates.

  • ivosidenib

    Serious – Use Alternative (1)ivosidenib will decrease the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sensitive CYP3A4 substrates with ivosidenib or replace with alternative therapies. If coadministration is unavoidable, monitor patients for loss of therapeutic effect of these drugs.

  • ketamine

    Monitor Closely (1)ketamine and metaxalone both increase sedation. Use Caution/Monitor.

  • ketotifen, ophthalmic

    Monitor Closely (1)metaxalone and ketotifen, ophthalmic both increase sedation. Use Caution/Monitor.

  • lasmiditan

    Monitor Closely (1)lasmiditan, metaxalone.
    Either increases effects of the other by sedation. Use Caution/Monitor. Coadministration of lasmiditan and other CNS depressant drugs, including alcohol have not been evaluated in clinical studies. Lasmiditan may cause sedation, as well as other cognitive and/or neuropsychiatric adverse reactions.

  • lemborexant

    Monitor Closely (1)lemborexant, metaxalone.
    Either increases effects of the other by sedation. Modify Therapy/Monitor Closely. Dosage adjustment may be necessary if lemborexant is coadministered with other CNS depressants because of potentially additive effects.

  • levorphanol

    Monitor Closely (1)metaxalone and levorphanol both increase sedation. Use Caution/Monitor.

  • lofepramine

    Monitor Closely (1)metaxalone and lofepramine both increase sedation. Use Caution/Monitor.

  • lofexidine

    Monitor Closely (1)metaxalone and lofexidine both increase sedation. Use Caution/Monitor.

  • lopinavir

    Serious – Use Alternative (1)lopinavir will increase the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

  • loprazolam

    Monitor Closely (1)loprazolam and metaxalone both increase sedation. Use Caution/Monitor.

  • lorazepam

    Monitor Closely (1)lorazepam and metaxalone both increase sedation. Use Caution/Monitor.

  • lorcaserin

    Monitor Closely (1)lorcaserin will increase the level or effect of metaxalone by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

  • lormetazepam

    Monitor Closely (1)lormetazepam and metaxalone both increase sedation. Use Caution/Monitor.

  • loxapine

    Monitor Closely (1)metaxalone and loxapine both increase sedation. Use Caution/Monitor.

  • loxapine inhaled

    Monitor Closely (1)metaxalone and loxapine inhaled both increase sedation. Use Caution/Monitor.

  • lurasidone

    Monitor Closely (1)lurasidone, metaxalone.
    Either increases toxicity of the other by Other (see comment). Use Caution/Monitor.
    Comment: Potential for increased CNS depressant effects when used concurrently; monitor for increased adverse effects and toxicity.

  • maprotiline

    Monitor Closely (1)metaxalone and maprotiline both increase sedation. Use Caution/Monitor.

  • marijuana

    Monitor Closely (1)metaxalone and marijuana both increase sedation. Use Caution/Monitor.

  • melatonin

    Monitor Closely (1)metaxalone and melatonin both increase sedation. Use Caution/Monitor.

  • meperidine

    Monitor Closely (1)metaxalone and meperidine both increase sedation. Use Caution/Monitor.

  • meprobamate

    Monitor Closely (1)metaxalone and meprobamate both increase sedation. Use Caution/Monitor.

  • methadone

    Monitor Closely (1)metaxalone and methadone both increase sedation. Use Caution/Monitor.

  • methocarbamol

    Monitor Closely (1)metaxalone and methocarbamol both increase sedation. Use Caution/Monitor.

  • methylenedioxymethamphetamine

    Monitor Closely (1)metaxalone increases and methylenedioxymethamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

  • metoclopramide intranasal

    Serious – Use Alternative (1)metaxalone, metoclopramide intranasal.
    Either increases effects of the other by Other (see comment). Avoid or Use Alternate Drug.
    Comment: Avoid use of metoclopramide intranasal or interacting drug, depending on importance of drug to patient.

  • midazolam

    Monitor Closely (1)midazolam and metaxalone both increase sedation. Use Caution/Monitor.

  • midodrine

    Monitor Closely (1)metaxalone increases and midodrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

  • mifepristone

    Monitor Closely (1)mifepristone will increase the level or effect of metaxalone by Other (see comment). Use Caution/Monitor. Inhibits CYP2C8/2C9; use smallest recommended doses for substrates and monitor

  • mirabegron

    Monitor Closely (1)mirabegron will increase the level or effect of metaxalone by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

  • mirtazapine

    Monitor Closely (1)metaxalone and mirtazapine both increase sedation. Use Caution/Monitor.

  • mitotane

    Monitor Closely (1)mitotane decreases levels of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Mitotane is a strong inducer of cytochrome P-4503A4; monitor when coadministered with CYP3A4 substrates for possible dosage adjustments.

  • morphine

    Monitor Closely (1)metaxalone and morphine both increase sedation. Use Caution/Monitor.

  • motherwort

    Monitor Closely (1)metaxalone and motherwort both increase sedation. Use Caution/Monitor.

  • moxonidine

    Monitor Closely (1)metaxalone and moxonidine both increase sedation. Use Caution/Monitor.

  • nabilone

    Monitor Closely (1)metaxalone and nabilone both increase sedation. Use Caution/Monitor.

  • nalbuphine

    Monitor Closely (1)metaxalone and nalbuphine both increase sedation. Use Caution/Monitor.

  • nefazodone

    Monitor Closely (1)nefazodone will increase the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

  • nortriptyline

    Monitor Closely (1)metaxalone and nortriptyline both increase sedation. Use Caution/Monitor.

  • olanzapine

    Monitor Closely (1)metaxalone and olanzapine both increase sedation. Use Caution/Monitor.

  • oliceridine

    Monitor Closely (2)oliceridine, metaxalone.
    Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

    metaxalone increases toxicity of oliceridine by Other (see comment). Modify Therapy/Monitor Closely.
    Comment: Anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Monitor for signs of urinary retention or reduced gastric motility if oliceridine is coadministered with anticholinergics.

  • opium tincture

    Monitor Closely (1)metaxalone and opium tincture both increase sedation. Use Caution/Monitor.

  • orphenadrine

    Monitor Closely (1)metaxalone and orphenadrine both increase sedation. Use Caution/Monitor.

  • oxazepam

    Monitor Closely (1)oxazepam and metaxalone both increase sedation. Use Caution/Monitor.

  • oxycodone

    Monitor Closely (1)metaxalone and oxycodone both increase sedation. Use Caution/Monitor.

  • oxymorphone

    Monitor Closely (1)metaxalone and oxymorphone both increase sedation. Use Caution/Monitor.

  • paliperidone

    Monitor Closely (1)metaxalone and paliperidone both increase sedation. Use Caution/Monitor.

  • papaveretum

    Monitor Closely (1)metaxalone and papaveretum both increase sedation. Use Caution/Monitor.

  • papaverine

    Monitor Closely (1)metaxalone and papaverine both increase sedation. Use Caution/Monitor.

  • pentazocine

    Monitor Closely (1)metaxalone and pentazocine both increase sedation. Use Caution/Monitor.

  • pentobarbital

    Monitor Closely (1)pentobarbital and metaxalone both increase sedation. Use Caution/Monitor.

  • perphenazine

    Monitor Closely (1)metaxalone and perphenazine both increase sedation. Use Caution/Monitor.

  • phenobarbital

    Monitor Closely (1)phenobarbital and metaxalone both increase sedation. Use Caution/Monitor.

  • phenylephrine PO

    Monitor Closely (1)metaxalone increases and phenylephrine PO decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. .

  • pholcodine

    Monitor Closely (1)metaxalone and pholcodine both increase sedation. Use Caution/Monitor.

  • pimozide

    Monitor Closely (1)metaxalone and pimozide both increase sedation. Use Caution/Monitor.

  • prabotulinumtoxinA

    Monitor Closely (1)metaxalone increases effects of prabotulinumtoxinA by pharmacodynamic synergism. Use Caution/Monitor. Muscle relaxants may enhance botulinum toxin effects. Closely monitor for increased neuromuscular blockade.

  • primidone

    Monitor Closely (1)primidone and metaxalone both increase sedation. Use Caution/Monitor.

  • prochlorperazine

    Monitor Closely (1)metaxalone and prochlorperazine both increase sedation. Use Caution/Monitor.

  • promethazine

    Monitor Closely (1)promethazine and metaxalone both increase sedation. Use Caution/Monitor.

  • propofol

    Monitor Closely (1)propofol and metaxalone both increase sedation. Use Caution/Monitor.

  • propylhexedrine

    Monitor Closely (1)metaxalone increases and propylhexedrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

  • protriptyline

    Monitor Closely (1)metaxalone and protriptyline both increase sedation. Use Caution/Monitor.

  • quazepam

    Monitor Closely (1)quazepam and metaxalone both increase sedation. Use Caution/Monitor.

  • quetiapine

    Monitor Closely (1)metaxalone and quetiapine both increase sedation. Use Caution/Monitor.

  • ramelteon

    Monitor Closely (1)metaxalone and ramelteon both increase sedation. Use Caution/Monitor.

  • remifentanil

    Monitor Closely (1)metaxalone increases effects of remifentanil by pharmacodynamic synergism. Modify Therapy/Monitor Closely. CNS depressant effect increased.

  • remimazolam

    Monitor Closely (1)remimazolam, metaxalone.
    Either increases toxicity of the other by sedation. Modify Therapy/Monitor Closely. Coadministration may result in profound sedation, respiratory depression, coma, and/or death. Continuously monitor vital signs during sedation and recovery period if coadministered. Carefully titrate remimazolam dose if administered with opioid analgesics and/or sedative/hypnotics.

  • ribociclib

    Minor (1)ribociclib will increase the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

  • risperidone

    Monitor Closely (1)metaxalone and risperidone both increase sedation. Use Caution/Monitor.

  • rucaparib

    Monitor Closely (1)rucaparib will increase the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Adjust dosage of CYP3A4 substrates, if clinically indicated.

  • sage

    Minor (1)metaxalone and sage both increase sedation. Minor/Significance Unknown.

  • scullcap

    Monitor Closely (1)metaxalone and scullcap both increase sedation. Use Caution/Monitor.

  • secobarbital

    Monitor Closely (1)secobarbital and metaxalone both increase sedation. Use Caution/Monitor.

  • shepherd’s purse

    Monitor Closely (1)metaxalone and shepherd’s purse both increase sedation. Use Caution/Monitor.

  • sodium oxybate

    Serious – Use Alternative (1)metaxalone, sodium oxybate.
    Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

  • stiripentol

    Monitor Closely (2)stiripentol, metaxalone.
    Either increases effects of the other by sedation. Use Caution/Monitor. Concomitant use stiripentol with other CNS depressants, including alcohol, may increase the risk of sedation and somnolence.

    stiripentol, metaxalone. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Stiripentol is a CYP3A4 inhibitor and inducer. Monitor CYP3A4 substrates coadministered with stiripentol for increased or decreased effects. CYP3A4 substrates may require dosage adjustment.

  • sufentanil

    Monitor Closely (1)metaxalone and sufentanil both increase sedation. Use Caution/Monitor.

  • sufentanil SL

    Serious – Use Alternative (1)sufentanil SL, metaxalone.
    Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration may result in hypotension, profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

  • tapentadol

    Monitor Closely (1)metaxalone and tapentadol both increase sedation. Use Caution/Monitor.

  • tazemetostat

    Monitor Closely (1)tazemetostat will decrease the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

  • tecovirimat

    Monitor Closely (1)tecovirimat will decrease the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Tecovirimat is a weak CYP3A4 inducer. Monitor sensitive CYP3A4 substrates for effectiveness if coadministered.

  • temazepam

    Monitor Closely (1)temazepam and metaxalone both increase sedation. Use Caution/Monitor.

  • teriflunomide

    Monitor Closely (2)teriflunomide increases levels of metaxalone by Other (see comment). Use Caution/Monitor.
    Comment: Teriflunomide inhibits CYP2C8; caution when coadministered with CYP2C8 substrates.

    teriflunomide decreases levels of metaxalone by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

  • thioridazine

    Monitor Closely (1)metaxalone and thioridazine both increase sedation. Use Caution/Monitor.

  • thiothixene

    Monitor Closely (1)metaxalone and thiothixene both increase sedation. Use Caution/Monitor.

  • topiramate

    Monitor Closely (1)metaxalone and topiramate both increase sedation. Modify Therapy/Monitor Closely.

  • tramadol

    Monitor Closely (1)metaxalone and tramadol both increase sedation. Use Caution/Monitor.

  • trazodone

    Monitor Closely (1)metaxalone and trazodone both increase sedation. Use Caution/Monitor.

  • triazolam

    Monitor Closely (1)triazolam and metaxalone both increase sedation. Use Caution/Monitor.

  • triclofos

    Monitor Closely (1)triclofos and metaxalone both increase sedation. Use Caution/Monitor.

  • trifluoperazine

    Monitor Closely (1)metaxalone and trifluoperazine both increase sedation. Use Caution/Monitor.

  • trimipramine

    Monitor Closely (1)metaxalone and trimipramine both increase sedation. Use Caution/Monitor.

  • tucatinib

    Serious – Use Alternative (1)tucatinib will increase the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid concomitant use of tucatinib with CYP3A substrates, where minimal concentration changes may lead to serious or life-threatening toxicities. If unavoidable, reduce CYP3A substrate dose according to product labeling.

  • voxelotor

    Serious – Use Alternative (1)voxelotor will increase the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Voxelotor increases systemic exposure of sensitive CYP3A4 substrates. Avoid coadministration with sensitive CYP3A4 substrates with a narrow therapeutic index. Consider dose reduction of the sensitive CYP3A4 substrate(s) if unable to avoid.

  • xylometazoline

    Monitor Closely (1)metaxalone increases and xylometazoline decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

  • ziconotide

    Monitor Closely (1)metaxalone and ziconotide both increase sedation. Use Caution/Monitor.

  • ziprasidone

    Monitor Closely (1)metaxalone and ziprasidone both increase sedation. Use Caution/Monitor.

  • zotepine

    Monitor Closely (1)metaxalone and zotepine both increase sedation. Use Caution/Monitor.

  • Differences, similarities, and which is better for you

    Drug overview & main differences | Conditions treated | Efficacy | Insurance coverage and cost comparison | Side effects | Drug interactions | Warnings | FAQ

    Have you ever “thrown out your back” or experienced an injury or sprain where you feel like your muscles are spasming and so tight that you can’t move? If so, your healthcare provider may have prescribed a muscle relaxant to help your symptoms.

    Skelaxin and Flexeril are two FDA-approved medications indicated to treat muscle spasms. They are in a group of medications called skeletal muscle relaxants. Skelaxin and Flexeril are most commonly prescribed as their generic counterparts, metaxalone and cyclobenzaprine. The way they work is not completely understood, but may be due to central nervous system (CNS) depression and sedative effects. These medications do not act directly on the muscle or nerves.

    Although both medications are muscle relaxants, they are not exactly the same. Continue reading below to learn more about Skelaxin and Flexeril.

    What are the main differences between Skelaxin and Flexeril?

    Skelaxin is a skeletal muscle relaxant that contains metaxalone. It is available in brand and generic tablets. Skelaxin is used for short-term treatment.

    Flexeril is also a skeletal muscle relaxant—the active ingredient is cyclobenzaprine. Flexeril is no longer available commercially as a brand-name product. Flexeril is only available as its generic, cyclobenzaprine. Cyclobenzaprine is also available in an extended-release form with the brand name of Amrix. Flexeril is used for short-term treatment—the manufacturer’s information recommends that Flexeril should not be taken for more than two or three weeks.

    Main differences between Skelaxin and Flexeril
    Drug class Skeletal muscle relaxant Skeletal muscle relaxant
    Brand/generic status Brand and generic Flexeril: available in generic only
    Amrix: available in brand and generic
    What is the generic name? Metaxalone Cyclobenzaprine
    What form(s) does the drug come in? Tablet Tablet, extended-release capsule (brand name Amrix)
    What is the standard dosage? The recommended dose is one (800 mg) tablet or two (400 mg) tablets 3 to 4 times daily The recommended dose is one tablet (5 mg or 10 mg) 3 times daily
    Or
    One tablet (5 mg, 7.5 mg, or 10 mg) at bedtime (less frequent dosing for patients with liver problems or elderly patients)
    How long is the typical treatment? Short-term Short-term (not recommended for more than 2-3 weeks)
    Who typically uses the medication? Adults and children over age 12 years Adults and children age 15 years and older

    Conditions treated by Skelaxin and Flexeril

    Skelaxin and Flexeril are both indicated to be used along with rest, physical therapy, and other measures to relieve the discomfort of acute, painful musculoskeletal conditions like acute low back pain or neck pain.

    Both drugs may be prescribed off-label for other conditions, but they are primarily used for muscle spasms. Also, the Flexeril manufacturer information states that the drug is not effective for spasticity associated with cerebral or spinal cord disease, or in children with cerebral palsy.

    Acute, painful musculoskeletal conditions Yes Yes
    Fibromyalgia Off-label Off-label
    Tension headache Off-label Off-label
    Insomnia Off-label Off-label
    Acute jaw pain from TMJ Off-label Off-label

    Is Skelaxin or Flexeril more effective?

    American Family Physician states that there is weak (and very little) evidence in terms of muscle relaxants and their efficacy compared to each other. They recommend that the selection of a muscle relaxant should be based on the potential for side effects, drug interactions, abuse, and also patient preference. This publication also reiterates the importance of short-term use of muscle relaxants and that physical therapy and other measures should be taken to prevent long-term use of a muscle relaxant. Other medications such as Tylenol (acetaminophen) or nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, may also be used.

    Your healthcare provider can determine if Skelaxin or Flexeril is appropriate for you. He or she will consider your symptoms, medical conditions, medical history, and any medications you take that may interact with Skelaxin or Flexeril.

    Coverage and cost comparison of Skelaxin vs. Flexeril

    Most insurance plans typically cover Skelaxin in its generic form of metaxalone. Medicare Part D coverage varies. A typical prescription of generic Skelaxin would have an out-of-pocket cost of $147, but you can use a SingleCare coupon to bring the price down to less than $50.

    Most insurance and Medicare Part D plans cover Flexeril (generic). Brand-name Flexeril is not available. A typical prescription of generic Flexeril would cost about $20 out-of-pocket, but with SingleCare you can purchase the generic Flexeril for about $7-$8 at participating pharmacies.

    Typically covered by insurance? Yes (generic) Yes (generic)
    Typically covered by Medicare Part D? No Yes (generic)
    Standard dosage 30, 800 mg tablets 30, 10 mg tablets
    Typical Medicare copay $1-$54, depending on the specific plan $0-$1
    SingleCare cost $48+ $7+

    Common side effects of Skelaxin vs. Flexeril

    Both drugs can be very sedating. Skelaxin’s most common side effects are drowsiness, dizziness, headache, irritability, nausea, vomiting, and stomach upset.

    The most common side effects of Flexeril are drowsiness, dizziness, headache, and dry mouth.

    With either drug, an allergic reaction is rare but possible. Serotonin syndrome, a life-threatening condition due to serotonin buildup, is also possible.

    Side effect Applicable? Frequency Applicable? Frequency
    Drowsiness Yes Not reported Yes 29-38%*
    Dizziness Yes Not reported Yes 11%
    Headache Yes Not reported Yes 5%
    Irritability Yes Not reported Yes 1-3%
    Nausea Yes Not reported Yes 1-3%
    Vomiting Yes Not reported Yes 1-3%
    Stomach upset Yes Not reported Yes 1-3%
    Dry mouth No Yes 21-32%

    *Side effect percentages of Flexeril depend on the dose

    Source: DailyMed (Skelaxin), DailyMed (Flexeril)

    Drug interactions of Skelaxin vs. Flexeril

    Skelaxin and Flexeril can potentiate the effects of alcohol, barbiturates, and other CNS depressants, such as benzodiazepines, opioids, antihistamines, and sedative-hypnotics.

    There is an increased risk of serotonin syndrome when Skelaxin or Flexeril is taken with other drugs that increase serotonin; such as SSRI, SNRI, or tricyclic antidepressants; triptans for migraine; or cough and cold medications that contain dextromethorphan.

    Flexeril is structurally similar to tricyclic antidepressants (such as amitriptyline and nortriptyline). Because of this, there is an increased risk of seizures when taken with tramadol.

    Both Skelaxin and Flexeril interact with tramadol (and other opioids)—there is an increased risk of serotonin syndrome as well as additive CNS depression.

    This is not a full list of drug interactions. Consult your healthcare provider for medical advice regarding drug interactions.

    Alcohol Alcohol Yes Yes
    Pentobarbital
    Phenobarbital
    Barbiturates Yes Yes
    Alprazolam
    Clonazepam
    Diazepam
    Lorazepam
    Temazepam
    Benzodiazepines Yes Yes
    Eszopiclone
    Zaleplon
    Zolpidem
    Sedative hypnotics Yes Yes
    Codeine
    Fentanyl
    Hydrocodone
    Hydromorphone
    Methadone
    Morphine
    Oxycodone
    Tramadol
    Opioids Yes Yes
    Phenelzine
    Selegiline
    Tranylcypromine
    MAO Inhibitors Yes
    Cetirizine
    Diphenhydramine
    Antihistamines Yes Yes
    Citalopram
    Escitalopram
    Fluoxetine
    Fluvoxamine
    Paroxetine
    Sertraline
    SSRI antidepressants Yes Yes
    Desvenlafaxine
    Duloxetine
    Venlafaxine
    SNRI antidepressants Yes Yes
    Amitriptyline
    Desipramine
    Imipramine
    Nortriptyline
    Tricyclic antidepressants Yes Yes
    Almotriptan
    Eletriptan
    Sumatriptan
    Zolmitriptan
    Triptans Yes Yes
    Delsym
    Phenergan-DM
    Robitussin-DM
    Tussin-DM
    OTC/Rx cough products that contain dextromethorphan Yes Yes

    Warnings of Skelaxin and Flexeril

    Skelaxin

    • Use Skelaxin with caution in elderly patients and patients with liver or kidney problems or anemia.
    • Taking Skelaxin with food may significantly increase the CNS depression effect. Elderly patients are more susceptible to this effect.

    Flexeril

    • Do not take an MAO inhibitor within 14 days of Flexeril—the combination could cause seizures and death.
    • Patients with hyperthyroidism, heart failure, or other heart or rhythm problems should not take Flexeril. Use Flexeril with caution in elderly patients and patients with liver problems. Do not use the extended-release form (Amrix) in patients with liver problems.
    • Use Flexeril with caution in patients with a history of urinary retention, angle-closure glaucoma, increased intraocular pressure, and in patients taking anticholinergic medication.
    • Consider withdrawal symptoms when discontinuing Flexeril. Stopping the medicine too quickly may cause headaches, fatigue, and nausea.
    • Swallow Amrix (extended-release cyclobenzaprine) capsules whole. Do not chew or crush.

    Skelaxin and Flexeril warnings in common

    • Both medications are on the list of Beers criteria, meaning that they are potentially inappropriate for older adults (age 65 and older). Most older adults do not tolerate muscle relaxants well due to serious side effects, sedation, and increased risk of fractures. Also, the effectiveness is questionable at the doses that may be tolerated in this age group.
    • Overdose deaths (deliberate or accidental) have occurred from Skelaxin or Flexeril, especially in combination with antidepressants or alcohol. Monitor patients closely.
    • Serotonin syndrome may occur. Patients and their caregivers should be aware of the symptoms (sweating, fever, agitation, change in blood pressure or heart rate, tremor, nausea, vomiting, diarrhea) and seek immediate medical attention if symptoms occur. Serotonin syndrome is more likely to occur if you take Skelaxin or Flexeril in combination with other drugs that increase serotonin, such as certain antidepressants, triptans, or cough and cold preparations that contain dextromethorphan.
    • Do not drive or operate machinery until you know how you react to Skelaxin or Flexeril. Both drugs cause drowsiness and dizziness.

    Frequently asked questions about Skelaxin vs. Flexeril

    What is Skelaxin?

    Skelaxin is a skeletal muscle relaxant used for the acute treatment of muscle spasms. The generic name for Skelaxin is metaxalone.

    What is Flexeril?

    Flexeril is also a muscle relaxant used to treat skeletal muscle spasms. The generic name of Flexeril is cyclobenzaprine.

    Are Skelaxin and Flexeril the same?

    Although Skelaxin and Flexeril are both in the same drug category (skeletal muscle relaxants), they do have some differences, such as side effects, dose, and pricing, as outlined above.

    Is Skelaxin or Flexeril better?

    No data directly compares the two drugs in terms of pain relief. Therefore, if you need a muscle relaxant, your healthcare provider will consider your symptoms, conditions, and any medications you take (that could interact with Skelaxin or Flexeril) to determine if one of these drugs is better for you.

    Can I use Skelaxin or Flexeril while pregnant?

    The Skelaxin manufacturer information states, “Post-marketing experience has not revealed evidence of fetal injury, but such experience cannot exclude the possibility of infrequent or subtle damage to the human fetus. Safe use of metaxalone has not been established with regard to possible adverse effects upon fetal development.” Therefore, Skelaxin is not recommended for use in pregnant women (especially in early pregnancy) or women who may become pregnant, unless your healthcare provider determines that benefits outweigh risks.

    The Flexeril manufacturer information states that there are no adequate, well-controlled studies in pregnant women. Therefore, Flexeril should be used in pregnant women only if clearly needed.

    Can I use Skelaxin or Flexeril with alcohol?

    No. Using Skelaxin or Flexeril with alcohol can increase the side effects such as dizziness and drowsiness. It can also lead to impaired coordination, which can cause accidents. Also, taking a muscle relaxant with alcohol can increase the chance of abuse or dependence.

    Is Skelaxin a strong muscle relaxer?

    Any muscle relaxant, including the following list, should be effective in treating acute muscle pain/spasms when used at the proper dose. Consult your healthcare provider for more information.

    Does Skelaxin help with pain?

    Yes, Skelaxin helps with the pain of acute muscle spasms. The manufacturer recommends using Skelaxin along with rest, physical therapy, and other measures. The way it works is not entirely understood but is likely due to central nervous system depression. Skelaxin does not directly work on the muscles or nerves.

    Is Skelaxin safe?

    Like any medication, Skelaxin has benefits as well as side effects and risks. See the Warnings section above for more information. If your healthcare provider has determined that Skelaxin is appropriate for you and is compatible with any medical conditions you have and medications you take, you will likely be able to safely take Skelaxin (for short-term use) with no significant issues. Consult your healthcare provider for medical advice.

    Metaxalone | Side Effects | Dosage | Precautions

    By Medicover Hospitals / 11 Mar 2021
    Home | Medicine | Metaxalone

    What is Metaxalone ?

  • Metaxalone is an analgesic that relaxes the muscles. It works by preventing nerve impulses (or pain sensations) from reaching the brain. Metaxalone is used to treat skeletal muscle conditions such as pain or injury in conjunction with rest and physical therapy.
    1. Metaxalone Uses
    2. Metaxalone Side effects
    3. Precautions
    4. Overdose
    5. Storage
    6. Metaxalone vs Tolperisone
    7. Frequently Asked Questions
    8. Citations

    Metaxalone Uses:

  • Metaxalone is a muscle relaxant that is used in conjunction with rest, physical therapy, and other measures to relax muscles and relieve pain and discomfort associated with strains, sprains, and other muscle injuries.
  • How to use Metaxalone?

  • As directed by your doctor, take this medication orally with or without food. Do not increase your dose or use this medication more frequently or for a longer period of time than prescribed. Your condition will not improve faster, and your chances of experiencing side effects will increase. If you experience any of the side effects after taking this medication after a high-fat meal, then take it on an empty stomach or take it after a light meal.
  • The dosage is dependent on your medical history and health condition as well as your response to treatment.
  • If your condition does not improve or gets worse, notify your doctor.
  • Metaxalone Side Effects:

  • Some of the common side effects of Metaxalone are:
    • Drowsiness
    • Dizziness
    • Upset stomach
    • Vomiting
    • Headache
    • Nervousness
    • Severe skin rash
    • Difficulty breathing
    • Yellowing of the skin or eyes
    • Unusual bruising or bleeding
    • Unusual tiredness
    • Weakness
    • Seizures
  • If you experience any of the above-mentioned symptoms, call your doctor immediately.
  • Precautions:

    • Tell your doctor or pharmacist if you are allergic to metaxalone or if you have any other allergies before taking it. Inactive ingredients might be present in this product and can cause allergic reactions or some other problems.
    • Inform your doctor or pharmacist about your medical history, particularly if you have: liver disease, kidney disease, anemia, or seizures, before using this medication.
    • This medication may cause dizziness or drowsiness. Alcohol can cause dizziness or drowsiness. Do not try driving, operate machinery, or do anything else that requires alertness until you are confident that you can do so safely. Consume no alcoholic beverages.
    • Older adults may be more sensitive to the drug’s side effects, particularly dizziness, drowsiness, or confusion. These side effects may increase the likelihood of a fall.
    • This medication should be used only when prescribed by your doctor during pregnancy. Consult your doctor about the possible risks and benefits.
    • It is not known whether this medication passes through breast milk or not. Before you start breastfeeding, talk to your doctor.

    Overdose:

  • If someone has taken an overdose of this medicine and has serious symptoms such as trouble breathing, seek medical advice immediately. Never take more doses than what is prescribed to you by your doctor.
  • Missed Dose:

  • It is necessary to take each dose of this medication on time. If you forget a dose, contact your doctor or pharmacist as soon as possible to arrange for a new dosing schedule. Do not double the dose.
  • Storage:

  • The medicine must not come in contact with heat, air, light and may damage it. The medicine must be kept in a safe place and far away from children’s reach.
  • Metaxalone Tolperisone
    Metaxalone is an analgesic that relaxes the muscles. Tolperisone Mydocalm) is a centrally-acting skeletal muscle relaxant used to treat increased muscle tone caused by neurological diseases.
    It is used to treat skeletal muscle conditions such as pain or injury in conjunction with rest and physical therapy. Tolperisone is used to relax muscles. It is employed in the treatment of acute musculoskeletal pain.
    It works by preventing nerve impulses (or pain sensations) from reaching the brain. It works on the brain and spinal cord centers to relieve muscle stiffness or spasm without reducing strength. This reduces pain and improves muscle movement.

    Frequently Asked Questions:

    It is a muscle relaxant that is used to relax the muscles and relieve pain or discomfort caused by strains, sprains, and other muscle injuries in conjunction with rest, physical therapy, and other measures.

    This medication may make you dizzy, drowsy, or less alert than usual. These effects may be amplified if you take this medication with food.

    Based on clinical studies, metaxalone (Skelaxin) has the fewest reported side effects and the lowest sedation potential of the muscle relaxants when taken as 800 mg tablets three to four times a day. Simply put, it is the most well-tolerated muscle relaxant.

    Metaxalone has a 1-hour onset of action, a 2 to 3-hour plasma half-life, and a 4 to 6-hour duration of action. This medication is available in 400-mg tablets with a recommended dose of 800 mg three or four times daily.

    It works for sohrt-term relief of low back pain and is equally effective.

    Metaxalone is contraindicated in patients with severely impaired hepatic and renal function. Because methylmalonic is metabolized by the liver and then eliminated by the kidney, both the parent drug and its metabolites may accumulate in such patients.

    Metaxalone belongs to the drug class skeletal muscle relaxants and is used to treat muscle spasms. The FDA has not classified the drug as safe to use during pregnancy. Under the Controlled Substances Act, metaxalone 800 mg is not a controlled substance.

    Skeletal muscle relaxants such as Skelaxin (metaxalone) and Flexeril (cyclobenzaprine) are used to treat painful muscle spasms. Similar Skelaxin and Flexeril side effects include drowsiness, dizziness, headache, nausea, and stomach upset or pain.

    Metaxalone is an analgesic that relaxes the muscles. It works by preventing nerve impulses (or pain sensations) from reaching the brain. Metaxalone is used to treat skeletal muscle conditions such as pain or injury in conjunction with rest and physical therapy.

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    Metaxalone tablets

    What is this medicine?

    METAXALONE (me TAX a lone) is a muscle relaxer. It is used to treat pain and stiffness in muscles caused by strains, sprains, or other injury.

    This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

    COMMON BRAND NAME(S): Metaxall, Skelaxin

    What should I tell my health care provider before I take this medicine?

    They need to know if you have any of these conditions:

    • anemia or blood disorder
    • kidney disease
    • liver disease
    • an unusual or allergic reaction to metaxalone, other medicines, foods, dyes, or preservatives
    • pregnant or trying to get pregnant
    • breast-feeding

    How should I use this medicine?

    Take this medicine by mouth. Swallow it with a full glass of water. Follow the directions on the prescription label. Do not take more medicine than you are told to take.

    Talk to your pediatrician regarding the use of this medicine in children. While this drug may be prescribed for children as young as 13 years of age for selected conditions, precautions do apply.

    Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

    NOTE: This medicine is only for you. Do not share this medicine with others.

    What if I miss a dose?

    If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

    What may interact with this medicine?

    Do not take this medication with any of the following medicines:

    • narcotic medicines for cough

    This medicine may also interact with the following medications:

    • alcohol
    • antihistamines for allergy, cough and cold
    • certain medicines for anxiety or sleep
    • certain medicines for depression like amitriptyline, fluoxetine, sertraline
    • certain medicines for seizures like phenobarbital, primidone
    • general anesthetics like halothane, isoflurane, methoxyflurane, propofol
    • local anesthetics like lidocaine, pramoxine, tetracaine
    • medicines that relax muscles for surgery
    • narcotic medicines for pain
    • phenothiazines like chlorpromazine, mesoridazine, prochlorperazine, thioridazine

    This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

    What should I watch for while using this medicine?

    Tell your doctor or health care professional if your symptoms do not start to get better or if they get worse.

    You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol may interfere with the effect of this medicine. Avoid alcoholic drinks.

    If you are taking another medicine that also causes drowsiness, you may have more side effects. Give your health care provider a list of all medicines you use. Your doctor will tell you how much medicine to take. Do not take more medicine than directed. Call emergency for help if you have problems breathing or unusual sleepiness.

    What side effects may I notice from receiving this medicine?

    Side effects that you should report to your doctor or health care professional as soon as possible:

    • allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
    • breathing problems
    • unusually weak or tired

    Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

    • anxious
    • headache
    • irritability
    • upset stomach

    This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

    Where should I keep my medicine?

    Keep out of the reach of children.

    Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Keep container tightly closed. Throw away any unused medicine after the expiration date.

    NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

    What is Metaxalon?

    Metaxalone is a prescription-only muscle relaxant that is most commonly used to treat trauma to the musculoskeletal system that results in pain such as sprains or muscle spasms. The drug is a central nervous system (CNS) depressant and may cause more severe sedative symptoms when combined with other CNS depressants. Doctors do not always consider this medication as the best choice and take into account the patient’s health conditions or prescribed medications that are contraindicated.In addition, metaxalone can cause minor or serious side effects in a small percentage of users.

    Metaxalone is available by prescription in most regions and is usually prescribed only to adults or children over 12 years of age. The usual dose is an 800 mg tablet, although less is sometimes recommended, every three to four hours. Younger children are not good candidates for this medication. Elderly patients usually don’t get it either, because CNS effects, such as dizziness, can be much more pronounced in this population.Pregnant and breastfeeding women should also not use this medication.

    There are certain medical conditions that may contraindicate the use of metaxalone. Those with anemia – an extremely low red blood cell count – are generally not advised to take this drug. Patients with sick or damaged liver or kidneys may need to use less of the drug or may need other medications to relieve pain.

    Drug interactions between metaxalone and other medications are numerous.The main interaction occurs when patients are taking propoxyphene of any kind. However, since many regions have banned the use of propoxyphene, it is less likely that anyone will experience this reaction.

    Using this medication with other drugs that are CNS depressants is likely to cause an increase in certain side effects. Those taking benzodiazepines, opioids, barbiturates, or antipsychotic medications should discuss the risks and benefits of taking them with metaxalone with their doctor.In addition, people should avoid mixing the drug with alcohol, which is also a CNS depressant.

    The side effects of metaxalone can be considered benign or serious. Some patients develop mild gastrointestinal distress such as vomiting, nausea, or indigestion. Others report rashes or headaches. Symptoms of CNS depression include dizziness and drowsiness, and drug users can also have paradoxical reactions such as anxiety.These side effects are usually benign, but should be reported if they worsen or interfere with daily activities.

    In contrast, serious adverse reactions require immediate medical attention. These include any signs of an allergy such as hives, shortness of breath, and swelling of the face, mouth, and tongue. Nausea with severe abdominal pain is a medical emergency, as is the presence of jaundice or fever. Patients should also get help if their urine is very dark, as this may indicate problems with kidney function.

    OTHER LANGUAGES

    Metaxalone oral administration: uses, side effects, interactions, pictures, warnings and dosing –

    Uses

    Uses

    Metaxalone is used to treat muscle spasms / pain. It is commonly used in conjunction with rest, physical therapy, and other treatments.

    How to use Metaxalon

    Take this medication by mouth with or without food as directed by your healthcare practitioner, usually 3-4 times a day.If you are taking this medication after a high-fat meal and are experiencing side effects, it is best to take this medication on an empty stomach or after a light meal.

    The dosage depends on your medical condition and response to treatment. Do not increase your dose or use this medication more often or for longer than prescribed. Your condition will not improve any faster and your risk of side effects will increase.

    Tell your doctor if your condition does not improve or if it worsens.

    Related Links

    What conditions does Metaxalon treat?

    Side effects

    Side effects

    Drowsiness, dizziness, nausea, vomiting, and upset stomach may occur. If any of these effects persist or worsen, tell your doctor or pharmacist right away.

    Remember that your doctor prescribed this medication for you because he or she thought the benefit to you was greater than the risk of side effects.Many people using this medication do not have serious side effects.

    Tell your doctor right away if you have any serious side effects, including: mental / mood changes (such as nervousness, irritability, confusion), signs of infection (such as fever, persistent sore throat), yellowing eyes / skin, unusual tiredness, dark urine.

    This medicine can increase serotonin and rarely causes a very serious condition called serotonin syndrome / toxicity.The risk is increased if you are also taking other drugs that increase serotonin levels, so tell your doctor or pharmacist about any drugs you are taking (see Drug Interactions section). Get immediate medical attention if you develop any of the following symptoms: rapid heartbeat, hallucinations, loss of coordination, severe dizziness, severe nausea / vomiting / diarrhea, muscle twitching, unexplained fever, unusual agitation / restlessness.

    A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching / swelling (especially of the face / tongue / throat), severe dizziness, trouble breathing.

    This is not a complete listing of potential side effects. If you notice other effects not listed above, ask your doctor or pharmacist.

    In the USA –

    Ask your doctor about side effects. You can report side effects to the FDA by calling 1-800-FDA-1088 or at www.fda.gov/medwatch.

    In Canada – Call your doctor for medical advice about side effects. You can report side effects to Health Canada at 1-866-234-2345.

    Related Links

    List the side effects of metaxalone by likelihood and severity.

    Precautions

    Precautions

    Before taking metaxalone, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients that may cause allergic reactions or other problems. Talk to your pharmacist for more details.

    Before using this medication, tell your doctor or pharmacist your medical history, especially about: liver disease, kidney disease, anemia, seizures.

    This medicine may make you dizzy or drowsy. Alcohol or marijuana can make you dizzy or drowsy. Do not drive, use machinery, or do anything that requires vigilance until you can do so safely. Avoid alcoholic beverages. Talk to your doctor if you are using marijuana.

    Before surgery, tell your doctor or dentist about all products you use (including prescription, non-prescription, and herbal products).

    The elderly may be more sensitive to the side effects of this drug, especially dizziness, drowsiness, or confusion. These side effects can increase your risk of falling.

    During pregnancy, this medication should only be used when needed. Discuss the risks and benefits with your doctor.

    It is unknown if this drug passes into breast milk. Talk to your doctor before breastfeeding.

    Related Links

    What should I know about pregnancy, breastfeeding, and prescribing metaxalone to children or the elderly?

    interactions

    interactions

    Drug interactions may alter how your medications work or increase your risk of serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription / over-the-counter drugs and herbal products) and share with your doctor and pharmacist.Do not start, stop, or change the dosage of any medication without your doctor’s approval.

    Tell your doctor or pharmacist if you are taking other drugs that cause drowsiness such as opioid pain or cough suppressants (eg codeine, hydrocodone), alcohol, marijuana, sleep or anxiety medications (eg alprazolam, lorazepam, zolpidem) , other muscle relaxants (such as carisoprodol, cyclobenzaprine), or antihistamines (such as cetirizine, diphenhydramine).

    Check the labels on all of your medicines (such as allergies or colds) because they may contain ingredients that cause drowsiness. Ask your pharmacist about the safe use of these products.

    The risk of serotonin syndrome / toxicity is increased if you are taking other drugs that increase serotonin levels. Some examples are street drugs like MDMA / ecstasy, St. John’s wort, some antidepressants (like SSRIs like fluoxetine / paroxetine, SNRIs like duloxetine / venlafaxine), and others.The risk of serotonin syndrome / toxicity may be more likely when you start or increase your dose of these drugs.

    This medication may interfere with certain lab tests (including certain urine glucose tests), which may cause false test results. Make sure laboratory staff and all of your doctors know you are using this drug.

    Related Links

    Does Metaxalone interact with other medications?

    overdose

    overdose

    If someone has overdose and has severe symptoms such as fainting or trouble breathing, call 911.If not, contact a Poison Control Center immediately. US residents can call their local poison control center at 1-800-222-1222. Residents of Canada can call the provincial poison control center. Overdose symptoms may include: severe drowsiness.

    Notes

    Do not share this medicine with others.

    This medicine was prescribed for your current condition only. Do not use it later for another medical condition, unless your doctor instructs you to do so.In this case, other medications may be required.

    Missed dose

    If you miss a dose, take it as soon as you remember. If it is close to your next dose, skip them and resume your normal dosing regimen. Don’t double your dose to catch up.

    Storage

    Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medicines out of the reach of children and pets.

    Do not flush medicines down the toilet or pour them down the drain unless directed to do so.Correctly discard this product when it has expired or is no longer needed. Check with your pharmacist or local waste disposal company. Last revised March 2018. Copyright (c) 2018 First Databank, Inc.

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    instructions for use, dosages, composition, analogs, side effects / Pillintrip

    and also PATIENT INFORMATION ).

    Carcinogenesis, mutagenesis, impaired fertility

    The carcinogenic potential of metaxalone has not been determined.

    Pregnancy

    Reproduction studies in rats have shown no evidence of impaired fertility or fetal damage due to metaxalone. Post-marketing experience has not shown any evidence of fetal injury, but such experience cannot exclude the possibility of rare or subtle damage to the human fetus. The safe use of metaxalone has not been demonstrated with respect to possible adverse effects on fetal development.Therefore, metaxalone tablets should not be used by women who are or may be pregnant, especially during early pregnancy, unless the doctor believes the potential benefits outweigh the potential dangers.

    Nursing mothers

    It is not known whether this drug is excreted in breast milk. In general, you should not be careful when taking medications, as many medications are excreted in breast milk.

    Pediatric use

    Safety and efficacy in children over 12 years of age have not been established.

    Overdose and Contraindications

    TRANSLATION

    Intentional or accidental overdose deaths have occurred in metaxalone, especially in combination with antidepressants, and this class of drugs has been reported in combination with alcohol.

    Serotonin syndrome has been reported when metaxalone was used at doses above the recommended dose of layers (see WARNINGS ).

    In the determination of LD 50 , progressive sedation, hypnosis and finally respiratory failure were found in rats and mice with increasing dosage.No LD can be found in dogs. 50 are determined because higher doses were emetic after 15-30 minutes.

    Treatment

    Gastric lavage and supportive care. It is recommended that you check with your Regional Gift Management Center.

    PRICE

    Hypersensitivity to the components of this product is known.

    Known tendency towards drug, hemolytic or other anemias.

    Significantly impaired renal or liver function.

    Clinical Pharmacology

    CLINICAL PHARMACOLOGY

    Mechanism of Action

    The mechanism of action of metaxalone in humans has not been established, but it can be attributed to general depression of the central nervous system.

    Metaxalon has no direct effect on the contractile mechanism of the striated muscle, motor end plate or nerve fiber.

    Pharmacokinetics

    The pharmacokinetics of metaxalone was studied in healthy adult volunteers after a single administration of metaxalone in a sober and well-fed environment at doses ranging from 400 to 800 mg.

    Absorption

    Peak plasma metaxalone concentrations occur approximately 3 hours after a 400 mg oral dose under sober conditions. The logarithmic concentrations of metaxalone then decrease with a terminal half-life of 9.0 ± 4.8 hours. Doubling the dose of Metaxalone from 400 mg to 800 mg results in an approximately proportional increase in metaxalone exposure, as evidenced by peak plasma concentrations (Cmax) and area under the curve (AUC). Dose proportionality at doses above 800 mg has not been studied.The absolute bioavailability of metaxalone is not known.

    The pharmacokinetic parameters of metaxalone with a single dose in two groups of healthy volunteers are shown in Table 1.

    Table 1: Average (% CV) pharmacokinetic parameters Metaxalone

    Dose (mg) C ml ng / ) Tmax (h) AUC∞ (ng & ml; h / ml) t½ (h) CL / F (L / h)
    400 1 983 (53) 3.3 (35) 7479 (51) 9.0 (53) 68 (50)
    800 2 1816 (43) 3.0 (39) 15044 (46) 8.0 (58) 66 (51)
    1 Subjects received 1×400 mg tablet sober (N = 42)
    2 Subjects received 2×400 mg tablets sober (N = 59)
    Food Effects

    A randomized, bidirectional, crossover study was conducted in 42 healthy volunteers (31 males, 11 females) who received a 400 mg metaxalone tablet sober and after a standard high-fat breakfast.Subjects ranged from 18 to 48 years old (mean age = 23.5 ± 5.7 years). Compared to sober states, the presence of food with a high fat content increased by 177.5% during administration of drug C and increased AUC (AUC0-t, AUC∞) by 123.5% and 115.4%, respectively. Time to peak concentration (Tmax) was also delayed (4.3 hours versus 3.3 hours), and the terminal half-life was reduced (2.4 hours versus 9.0 hours) under feeding versus fasting.

    In a second study with a similar effect, healthy volunteers (N = 59, 37 men, 22 women) were given two tablets of metaxalone 400 mg (800 mg) at the age of 18-50 years (mean age = 25).6 ± 8.7 years). Compared with sober states, the presence of food with a high fat content increased by 193.6% during administration of drug C and increased AUC (AUC0-t, AUC, ∞) by 146.4% and 142.2%, respectively. Time to peak the concentration (Tmax) was also delayed (4.9 hours versus 3.0 hours) and the terminal half-life was shortened (4.2 hours versus 8.0 hours) under feeding versus fasting conditions. Similar nutritional effects were observed in the aforementioned study when a Metaxalone tablet was administered instead of two 400 mg Metaxalone tablets.An increase in metaxalone exposure, which coincides with a decrease in half-life, may be due to more complete absorption of metaxalone in the presence of a high-fat diet (Figure 1).

    Figure 1: Mean (SD) concentrations of metaxalone after 800 mg dose under fasting and feeding conditions

    Distribution, metabolism and excretion

    Although plasma protein binding and absolute bioavailability of metaxalone are unknown, the apparent volume of distribution (V / F ~ 800 L) and lipophilia (log P = 2.42) of metaxalone indicate that the drug is mainly distributed in tissues.Metaxalone is metabolized in the liver and excreted in the urine as unidentified metabolites. Hepatic cytochrome P450 enzymes play a role in the metabolism of metaxalone. In particular, CYP1A2, CYP2D6, CYP2E1 and CYP3A4 and to a lesser extent CYP2C8, CYP2C9 and CYP2C19 metabolize metaxalone.

    Metaxalones do not significantly inhibit major CYP enzymes such as CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1 and CYP3A4. Metaxalone does not induce significant induction of important CYP enzymes such as CYP1A2, CYP2B6 and CYP3A4 in vitro .

    Pharmacokinetics in special population groups
    Age

    The effect of age on the pharmacokinetics of metaxalone was determined after one administration of two tablets of 400 mg (800 mg) under fasting and feeding conditions. The results were evaluated separately and also in combination with the results of three other studies. Using the combined data, the results show that the pharmacokinetics of metaxalone under sober conditions is significantly more dependent on age than under feeding, with bioavailability increasing with age under sober conditions.

    Bioavailability of metaxalone under fasting and feeding conditions in three groups of healthy volunteers of different ages is shown in Table 2.

    Table 2: Average pharmacokinetic parameters (% CV) After a single administration of two tablets of metaxalone 400 mg (800 mg) under fasting conditions and feeding

    Age (years) Junior volunteers Elderly volunteers
    25.6 ± 8.7 39.3 ± 10.8 71.5 ± 5.0
    N 59 21 23
    Food Tasty Fed Tasty Fed Tasty ml 1816 (43) 3510 (41) 2719 (46) 2915 (55) 3168 (43) 36 80 (59)
    TMAX (h) 3.0 (39) 4.9 (48) 3.0 (40) 8.7 (91) 2.6 ( 30) 6.5 (67)
    AUC0-t (ng • h / ml) 14531 (47) 20683 (41) 19836 (40) 20482 (37) 23797 (45) 24340 (48)
    AUC∞ (ng • h / ml) 15045 (46) 20833 (41) 20490 (39) 20815 (37) 24194 (44) 24704 (47)
    Sex

    The effect of gender on the pharmacokinetics of metaxalone was evaluated in an open-label study in which 48 healthy adults (24 men, 24 women) were administered two 400 mg metaxalone tablets (800 mg) under sober conditions.