Lornoxicam

Lornoxicam

File:Lornoxicam 2.png
Systematic (IUPAC) name
(3E)-6-chloro-3-[hydroxy(pyridin-2-ylamino)methylene]-2-methyl-2,3-dihydro-4H-thieno[2,3-e][1,2]thiazin-4-one 1,1-dioxide
Identifiers
ATC code	M01AC05 (WHO)
PubChem	CID 5282204
Chemical data
Formula	C13H10ClN3O4S2
Molar mass	371.8192 g/mol[[]]

Lornoxicam (chlortenoxicam) is a non-steroidal anti-inflammatory drug (NSAID) of the oxicam class with analgesic, anti-inflammatory and antipyretic properties. It is available in oral and parenteral formulations.

Indications

• Inflammatory diseases of the joints
• Osteoarthritis
• Pain following surgery
• Sciatica

Mode of action

Like other NSAIDs, lornoxicam inhibits prostaglandin biosynthesis by blocking the enzyme cyclooxygenase.

Lornoxicam inhibits both isoforms in the same concentration range, that is, COX-1 inhibition : COX-2 inhibition = 1. It readily penetrates into the synovial fluid. Synovial fluid : plasma AUC ratio is 0.5 after administration of 4 mg twice daily.

Pharmacokinetics

Absorption

Lornoxicam is absorbed rapidly and almost completely from the gastro-intestinal tract. Maximum plasma concentrations are achieved after approximately 1 to 2 hours.

Distribution

The absolute bioavailability of Lornoxicam is 90–92%. No first-pass effect was observed.

Metabolism

Lornoxicam is found in the plasma in unchanged form and as its hydroxylated metabolite. The hydroxylated metabolite exhibits no pharmacological activity. CYP2C9 has been shown to be the primary enzyme responsible for the biotransformation of the lornoxicam to its major metabolite, 5’-hydroxylor noxicam. Recently, it was reported that lornoxicam 5’-hydroxylation by the variant CYP2C9*3 and CYP2C9*13 was markedly reduced compared with wild type, both in vitro and in vivo.

Elimination

Approximately 2/3 is eliminated via the liver and 1/3 via the kidneys as inactive substance.

Three of the most commonly employed substrate probes for determining CYP2C9 activity in crude human tissue fractions are (S)-warfarin (7-hydroxylation), tolbutamide (methylhydroxylation), and diclofenac (4-hydroxylation). And the best in vivo probes for CYP2C9 activity are tolbutamide and flurbiprofen. Turnover of (S)-warfarin and tolbutamide by CYP2C9 is extremely slow. Conversely, diclofenac has the advantage that CYP2C9 catalyzes its metabolism with a high turnover number, but is not a useful in vivo probe for the CYP2C9 enzyme.

Drug interactions

• Anticoagulants
• Sulphonylureas
• Diuretics, ACE inhibitors, digoxin
• Lithium
• Methotrexate, ciclosporin
• Cimetidine

Dosage

8 mg to 16 mg per day in 2 to 3 doses. The total daily dose should not exceed 16 mg.

Brand names

• Lornoxi
• Lorna tablets
• Lornex
• Lornox
• Lornasafe PLUS
• Lorsaid injection
• LRN tablets and injections
• Nyox tablets
• Xefo Rapid tablets
• Xefocam tablets and injection
• Zeficam

References

it:Lornoxicam