Clinical data
ATC code
Legal status
Legal status
Pharmacokinetic data
Protein binding36%
Elimination half-life17–20 hours
  • (S)-N-Ethyl-1-[3-(trifluoromethyl)phenyl]-propan-2-amine
CAS Number
PubChem CID
Chemical and physical data
Molar mass231.262 g·mol−1
3D model (JSmol)
  • FC(F)(F)c1cccc(c1)C[C@@H](NCC)C
  • InChI=1S/C12H16F3N/c1-3-16-9(2)7-10-5-4-6-11(8-10)12(13,14)15/h4-6,8-9,16H,3,7H2,1-2H3/t9-/m0/s1 checkY

Dexfenfluramine, marketed as dexfenfluramine hydrochloride under the name Redux, is a serotonergic anorectic drug: it reduces appetite by increasing the amount of extracellular serotonin in the brain.[3] It is the d-enantiomer of fenfluramine and is structurally similar to amphetamine, but lacks any psychologically stimulating effects.

Dexfenfluramine was, for some years in the mid-1990s, approved by the United States Food and Drug Administration for the purposes of weight loss. However, following multiple concerns about the cardiovascular side-effects of the drug,[3] the FDA withdrew the approval in 1997.[4] After it was removed in the US, dexfenfluramine was also pulled out in other global markets. It was later superseded by sibutramine, which, although initially considered a safer alternative to both dexfenfluramine and fenfluramine,[5][6][7] was likewise removed from the US market in 2010.[8][9]

The drug was developed by Interneuron Pharmaceuticals, a company co-founded by Richard Wurtman, aimed at marketing discoveries by Massachusetts Institute of Technology scientists.[10] Interneuron licensed the patent to Wyeth-Ayerst Laboratories.[11] Although at the time of its release, some optimism prevailed that it might herald a new approach,[12] there remained some reservations amongst neurologists, twenty-two of whom petitioned the FDA to delay approval.[citation needed] Their concern was based on the work of George A. Ricaurte, whose techniques and conclusions were later questioned.[13]

See also


  1. ^ "FDA-sourced list of all drugs with black box warnings (Use Download Full Results and View Query links.)". FDA. Retrieved 22 October 2023.
  2. ^ Anvisa (24 July 2023). "RDC Nº 804 - Listas de Substâncias Entorpecentes, Psicotrópicas, Precursoras e Outras sob Controle Especial" [Collegiate Board Resolution No. 804 - Lists of Narcotic, Psychotropic, Precursor, and Other Substances under Special Control] (in Brazilian Portuguese). Diário Oficial da União (published 25 July 2023). Archived from the original on 27 August 2023. Retrieved 27 August 2023.
  3. ^ a b Fox SI (2011). Human Physiology (Twelfth ed.). McGraw Hill. p. 665.
  4. ^ FDA 15 September 1997. FDA Announces Withdrawal Fenfluramine and Dexfenfluramine (Fen-Phen)
  5. ^ "Dexfenfluramine". PubChem. U.S. Library of Medicine. Retrieved 29 March 2023.
  6. ^ Hanotin C, Thomas F, Jones SP, Leutenegger E, Drouin P (July 1998). "A comparison of sibutramine and dexfenfluramine in the treatment of obesity". Obesity Research. 6 (4): 285–291. doi:10.1002/j.1550-8528.1998.tb00351.x. PMID 9688105.
  7. ^ Lean ME (March 1997). "Sibutramine--a review of clinical efficacy". International Journal of Obesity and Related Metabolic Disorders. 21 (Suppl 1): S30–6, discussion 37–9. PMID 9130039.
  8. ^ "Abbott Pulls Diet Drug Meridia Off US Shelves". The Wall Street Journal. 8 October 2010. Archived from the original on 23 October 2010.
  9. ^ Li MF, Cheung BM (February 2011). "Rise and fall of anti-obesity drugs". World Journal of Diabetes. 2 (2): 19–23. doi:10.4239/wjd.v2.i2.19. PMC 3083904. PMID 21537456.
  10. ^ Lemonick MD, Dowell W, Nash JM, Ramirez A, Reid B, Ressner J (23 September 1996). "The New Miracle Drug?". Time. Archived from the original on 6 November 2010. Retrieved 3 October 2010.
  11. ^ Lemonick MD, Nash JM, Park A, Thompson D (29 September 1997). "The Mood Molecule". Time. Archived from the original on 3 October 2008. Retrieved 4 October 2010.
  12. ^ Davis R, Faulds D (November 1996). "Dexfenfluramine. An updated review of its therapeutic use in the management of obesity". Drugs. 52 (5): 696–724. doi:10.2165/00003495-199652050-00007. PMID 9118819. S2CID 261029109.
  13. ^ Philipkoski K (2 March 2004). "DEA Accedes to Ecstasy Test". Wired. Archived from the original on 10 January 2006.