Oxicam Explained

Oxicam is a class of non-steroidal anti-inflammatory drugs (NSAIDs),^[1] meaning that they have anti-inflammatory, analgesic, and antipyretic therapeutic effects. Oxicams bind closely to plasma proteins.^[2] Most oxicams are unselective inhibitors of the cyclooxygenase (COX) enzymes. The exception is meloxicam with a slight (10:1) preference for COX-2, which, however, is only clinically relevant at low doses.^[3]

The most popular drug of the oxicam class is piroxicam.^[2] Other examples include: ampiroxicam, droxicam, pivoxicam, tenoxicam, lornoxicam,^[2] and meloxicam.

Isoxicam has been suspended as a result of fatal skin reactions.^[2]

Chemistry

The physico-chemical characteristics of these molecules vary greatly depending upon the environment.^[4]

In contrast to most other NSAIDs, oxicams are not carboxylic acids. They are tautomeric, and can exist as a number of tautomers (keto-enol tautomerism), here exemplified by piroxicam:^[1]

Side effects

The oxicams are associated with drug-related erythema multiforme (EM), Stevens–Johnson syndrome, and toxic epidermal necrolysis (TEN). This association is one of the reasons oxicams are not regularly prescribed.

References

1. Ivanova D, Deneva V, Nedeltcheva D, Kamounah FS, Gergov G, Hansen PE, Kawauchi S, Antonov L. March 2015. Tautomeric transformations of piroxicam in solution: a combined experimental and theoretical study. RSC Advances. Royal Society of Chemistry. England, UK. 5. 31852–31860. 40. 10.1039/c5ra03653d. 2015RSCAd...531852I . free.
2. Olkkola KT, Brunetto AV, Mattila MJ. February 1994. Pharmacokinetics of oxicam nonsteroidal anti-inflammatory agents. Clinical Pharmacokinetics. 26. 2. 107–20. 8162655. 10.2165/00003088-199426020-00004. 13300943 .
3. Book: Mutschler, Ernst. Gerd Geisslinger. Heyo K. Kroemer. Monika Schäfer-Korting. 2001. Mutschler Arzneimittelwirkungen: Lehrbuch der Pharmakologie und Toxikologie ; mit einführenden Kapiteln in die Anatomie, Physiologie und Pathophysiologie. German. Mutster medicine effects: Textbook of pharmacology and toxicology; with introductory chapters in anatomy, physiology and pathophysiology. Wissenschaftliche Verlagsgesellschaft. Stuttgart, Germany. 8. 233. 3-8047-1763-2. 12928661M. 48723029.
4. Banerjee R, Chakraborty H, Sarkar M. April 2003. Photophysical studies of oxicam group of NSAIDs: piroxicam, meloxicam and tenoxicam. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy. Elsevier. 59. 6. 1213–22. 2003AcSpA..59.1213B. 10.1016/S1386-1425(02)00300-1. 12659890.