Loxoprofen

Clinical data
AHFS/Drugs.com	International Drug Names
Routes of administration	Oral, transdermal
ATC code	M02AA31 (WHO)
Legal status
Legal status	JP: Class 1 OTC BR: Red Stripe (Rx only)
Pharmacokinetic data
Protein binding	97%
Metabolism	Liver glucuronidation
Elimination half-life	75 minutes
Excretion	Kidney
Identifiers
IUPAC name (RS)-2-{4-[(2-oxocyclopentyl)methyl]phenyl}propanoic acid
CAS Number	68767-14-6 N
PubChem CID	3965
DrugBank	DB09212 Y
ChemSpider	3828 Y
UNII	3583H0GZAP
KEGG	D08149 Y
ChEBI	CHEBI:76172 N
ChEMBL	ChEMBL19299 Y
CompTox Dashboard (EPA)	DTXSID1045164
Chemical and physical data
Formula	C15H18O3
Molar mass	246.306 g·mol−1
3D model (JSmol)	Interactive image
Chirality	Racemic mixture
SMILES O=C2C(Cc1ccc(cc1)C(C(=O)O)C)CCC2
InChI InChI=1S/C15H18O3/c1-10(15(17)18)12-7-5-11(6-8-12)9-13-3-2-4-14(13)16/h5-8,10,13H,2-4,9H2,1H3,(H,17,18) Y Key:YMBXTVYHTMGZDW-UHFFFAOYSA-N Y
NY (what is this?)  (verify)

Loxoprofen is a nonsteroidal anti-inflammatory drug (NSAID) in the propionic acid derivatives group, which also includes ibuprofen and naproxen among others. It is available in some countries for oral administration. A transdermal preparation was approved for sale in Japan in January 2006;^[1] medicated tape and gel formulations followed in 2008 and 2010.

It was patented in 1977 and approved for medical use in 1986.^[2]

Pharmacokinetics

Loxoprofen is a prodrug. It is quickly converted to its active trans-alcohol metabolite following oral administration, and reaches its peak plasma concentration within 30 to 50 minutes.

Mechanism of action

As most NSAIDs, loxoprofen is a non-selective cyclooxygenase inhibitor, and works by reducing the synthesis of prostaglandins from arachidonic acid.

Interactions

Loxoprofen should not be administered at the same time as second-generation quinolone antibiotics such as ciprofloxacin and norfloxacin, as it increases their inhibition of GABA and this may cause seizures.^[3] It may also increase the plasma concentration of warfarin, methotrexate, sulfonylurea derivatives and lithium salts, so care should be taken when loxoprofen is administered to patients taking any of these drugs.^[3]

Brand names

It is marketed in Brazil, Mexico, China and Japan by Sankyo as its sodium salt, loxoprofen sodium, under the trade name Loxonin; in Argentina as Oxeno; in India as Loxomac; in Thailand as Japrolox; and in Saudi Arabia as Roxonin and Roxonin Tape.

A generic drug is marketed in Brazil by Aché as Oxotron. In Japan, two fixed dose combinations are available: Loxonin S Plus, with magnesium oxide, and Loxonin S Premium, with apronal, caffeine, and aluminium magnesium silicate.