![]() | |
Clinical data | |
---|---|
Trade names | Skelaxin |
AHFS/Drugs.com | Monograph |
MedlinePlus | a682010 |
License data |
|
Routes of administration | By mouth |
ATC code |
|
Legal status | |
Legal status | |
Pharmacokinetic data | |
Bioavailability | Unknown |
Metabolism | Liver |
Elimination half-life | 9.2 (± 4.8) hours |
Excretion | Kidney |
Identifiers | |
| |
CAS Number | |
PubChem CID | |
IUPHAR/BPS | |
DrugBank | |
ChemSpider | |
UNII | |
KEGG | |
ChEMBL | |
CompTox Dashboard (EPA) | |
ECHA InfoCard | 100.015.253 |
Chemical and physical data | |
Formula | C12H15NO3 |
Molar mass | 221.256 g·mol−1 |
3D model (JSmol) | |
| |
| |
(verify) |
Metaxalone, sold under the brand name Skelaxin, is a muscle relaxant medication used to relax muscles and relieve pain caused by strains, sprains, and other musculoskeletal conditions.[1] Its exact mechanism of action is not known, but it may be due to general central nervous system depression.[1] It is a moderately strong muscle relaxant, with relatively low incidence of side effects.[citation needed]
Common side effects include nausea, vomiting, drowsiness, and central nervous system (CNS) side effects, such as dizziness, headache, and irritability.[1]
The metabolism of metaxalone involves enzymes CYP1A2 and CYP2C19 in the cytochrome P450 system.[medical citation needed] Because many medications are metabolized by enzymes in this system, precaution must be taken when administering it with other medications involving the P450 system to avoid interactions.[2]
Because of the potential for side effects, this drug is considered a high risk in the elderly.[medical citation needed]
Metaxalone exhibits increased bioavailability when taken with food.[3] Specifically, in one study, compared to fasted conditions, the presence of food at the time of drug administration increased Cmax by 77.5%, AUC0-t by 23.5%, and AUC0-∞ by 15.4%.[4] Metaxalone is a substrate of CYP1A2 and CYP2C19, an inhibitor of CYP1A2, CYP2B6, CYP2C9, CYP2C19, CYP2D6, CYP2E1, and CYP3A, and an inducer of CYP1A2 and CYP3A4.[2]
A literature survey reveals very few methods are reported for the determination of metaxalone to date. Nirogi et al.[4] reported a liquid chromatographic method coupled to tandem mass spectrometry for the quantification of metaxalone in human plasma. A stability-indicating HPLC method was introduced by P.K. Sahu et al.[5] Metaxalone has been used as an internal standard for few analytical methods.[6][7]