Tolfenamic acid (Clotam, Tufnil, TFA) is a member of the anthranilic acid derivatives (or fenamate) class of NSAID drugs.[2] Like other members of the class, it is a COX inhibitor and prevents formation of prostaglandins.[3]
It is used in the UK as a treatment for migraine.[4][5] It is generally not available in the US.[3] It is available in some Asian, Latin American and European countries as a generic drug for humans and for animals.[6]
TFA, like other non-steroidal anti-inflammatory drugs (NSAIDs), finds utility in the prevention and treatment of conditions associated with pain and inflammation.[7][8] However, despite its efficacy when administered intramuscularly, subcutaneously, or orally,[9] TFA-based drugs have not yet gained approval in the United States and some other countries due to the significant number of reported side effects.[10][11]
Nevertheless, TFA exhibits promise in medical practice, demonstrating the ability to inhibit the growth of cancer cells in the pancreas, sigmoid colon, and rectum.[12] Further research and development may unveil its potential for therapeutic applications in the future.
Tolfenamic acid, belonging to the pharmacological group of fenamates, possesses a chemical structure typical of anthranilic acid derivatives. In this structure, one of the hydrogen atoms of the nitro group is substituted by a benzene ring featuring a methyl group and a chlorine atom at the ortho- and meta- positions, respectively.[13]
Currently, nine forms of TFA have been identified, some of which are determined by conformational states.[14][15][16] These polymorphic forms exhibit variations in the spatial arrangement within the unit cell and in the values of the C-N(H)-C-C angle.[16] This diversity in solid forms makes TFA an attractive candidate for modification and utilization in medical applications.
^ abPentikäinen PJ, Neuvonen PJ, Backman C (1981). "Human pharmacokinetics of tolfenamic acid, a new anti-inflammatory agent". European Journal of Clinical Pharmacology. 19 (5): 359–365. doi:10.1007/bf00544587. PMID7238564. S2CID9428076.
^ abNIH LiverTox Database Mefenamic Acid Last updated June 23, 2015. Page accessed July 3, 2015. Quote: "(fenamates generally not available in the United States, such as tolfenamic acid and flufenamic acid)"
^Kajander A, Laine V, Gothoni G (January 1972). "Effect of tolfenamic acid in rheumatoid arthritis". Scandinavian Journal of Rheumatology. 1 (2): 91–93. doi:10.3109/03009747209103003. PMID4572954.
^Basha R, Baker CH, Sankpal UT, Ahmad S, Safe S, Abbruzzese JL, et al. (January 2011). "Therapeutic applications of NSAIDS in cancer: special emphasis on tolfenamic acid". Frontiers in Bioscience. 3 (2): 797–805. doi:10.2741/s188. PMID21196413.
^Corum O, Corum DD, Er A, Yildiz R, Uney K (December 2018). "Pharmacokinetics and bioavailability of tolfenamic acid in sheep". Journal of Veterinary Pharmacology and Therapeutics. 41 (6): 871–877. doi:10.1111/jvp.12702. PMID30084126. S2CID51930602.
^Kjaersgård Rasmussen MJ, Holt Larsen B, Borg L, Soelberg Sørensen P, Hansen PE (June 1994). "Tolfenamic acid versus propranolol in the prophylactic treatment of migraine". Acta Neurologica Scandinavica. 89 (6): 446–450. doi:10.1111/j.1600-0404.1994.tb02664.x. PMID7976233. S2CID12334561.