FDA label 9d31087a-20db-4628-9e11-3ca2b9c823e1

openFDA label record#

This page contains supplementary openFDA label data. For the canonical label presentation, use the corresponding DailyMed Structured Product Label.

Verified complete openFDA source JSON (canonical bytes are SHA-256 checked before publication)

SPL set ID
c0882edb-e2ad-470e-b26d-3c83b657abf9
SPL ID
9d31087a-20db-4628-9e11-3ca2b9c823e1
Version
10
Effective date
2026-06-17
Source export date
2026-09-28
Source partition
14
Source file
https://download.open.fda.gov/drug/label/drug-label-0014-of-0014.json.zip
Source object key
raw/openfda/drug-label/2026-09-28/db99fd80353afecef4949b48edcaa018be72b966b2360184251eb14df43743f9/drug-label-0014-of-0014.json.zip
Source manifest SHA-256
cd2e66336a5cd2223fa3995098fdbdb84c6a7ee5c0a4addb236ccb22dd1e6887
Import run
20260929T050834Z
Imported at
2026-09-29 06:39:54

Warnings cross-check#

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Warnings sections page 1 of 1 · 1 matching rows.

warnings

WARNINGS Serotonin Syndrome Cases of serotonin syndrome, a potentially life-threatening condition, have been reported during concomitant use of serotonergic drugs with metaxalone used within the recommended dosage range (see ) and with metaxalone as a single agent taken at doses higher than the recommended dose (see ). Serotonergic drugs include selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), triptans, 5-HT3 receptor antagonists, opioids (particularly fentanyl, meperidine, and methadone), drugs that affect the serotonergic neurotransmitter system (e.g., mirtazapine, trazodone, tramadol), and drugs that impair metabolism of serotonin (including monoamine oxidase (MAO) inhibitors, both those intended to treat psychiatric disorders and also others, such as linezolid and intravenous methylene blue) (see ). Serotonin syndrome symptoms may include mental status changes (e.g., agitation, hallucinations, coma), autonomic instability (e.g., tachycardia, labile blood pressure, hyperthermia), neuromuscular aberrations (e.g., hyperreflexia, incoordination, rigidity), and/or gastrointestinal symptoms (e.g., nausea, vomiting, diarrhea). The onset of symptoms generally occurs within several hours to a few days, but may occur later than that. Discontinue metaxalone if serotonin syndrome is suspected. Risks from Concomitant Use with Alcohol or other CNS Depressants The sedative effects of metaxalone and other CNS depressants (e.g., alcohol, benzodiazepines, opioids, tricyclic antidepressants (TCAs)) may be additive. Exercise caution with patients who take more than one of these CNS depressants simultaneously. Follow patients closely for signs and symptoms of respiratory depression and sedation (see ).

Adverse reactions cross-check#

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Adverse reactions sections page 1 of 1 · 1 matching rows.

adverse reactions

ADVERSE REACTIONS The most frequent reactions to metaxalone include: CNS : drowsiness, dizziness, headache, and nervousness or “irritability”; Digestive : nausea, vomiting, gastrointestinal upset. Other adverse reactions are: Immune System : anaphylaxis, hypersensitivity reaction, rash with or without pruritus; Hematologic : leukopenia; hemolytic anemia; Hepatobiliary : jaundice; CNS : cases of serotonin syndrome, a potentially life-threatening condition, have been reported during concomitant use of serotonergic drugs with metaxalone used within the recommended dosage range and with metaxalone as a single agent taken at doses higher than the recommended dose (see , , and ). To report SUSPECTED ADVERSE REACTIONS, contact Actavis at 1-888-838-2872 or FDA at 1-800-FDA-1088 www.fda.gov/medwatch.

Reported adverse events (FAERS/openFDA)#

Adverse event summaries are temporarily unavailable. Other product information remains available.