Nefopam

Nefopam

Systematic (IUPAC) name
5-methyl-1-phenyl-1,3,4,6-tetrahydro-2,5-benzoxazocine
Clinical data
AHFS/Drugs.com	International Drug Names
Pregnancy cat.	?
Legal status	Uncontrolled
Routes	Oral, Intravenous
Identifiers
CAS number	13669-70-0 Y
ATC code	N02BG06
PubChem	CID 4450
UNII	4UP8060B7J Y
KEGG	D08258 Y
Chemical data
Formula	C17H19NO
Mol. mass	253.34 g/mol
Y(what is this?)  (verify)

Nefopam (Acupan) is a centrally-acting but non-opioid analgesic drug of the benzoxazocine chemical class which was developed by Riker Laboratories in the 1960s^[1]. It is widely used, mainly in European countries, for the relief of moderate to severe pain as an alternative to opioid analgesic drugs. Animal studies have shown that nefopam has a potentiating (analgesic-sparing) effect on morphine and other opioids by broadening the antinociceptive action of the opioid and possibly other mechanisms, generally lowering the dose requirements of both when they are used concomitantly.^[2]

Use

Nefopam has additional action in the prevention of shivering, which may be a side effect of other drugs used in surgery.^[3]

Nefopam at a dose of 30–120 mg is significantly more effective than aspirin as an analgesic,^[4] although with a greater incidence of side effects such as sweating, dizziness and nausea, especially at higher doses.^[5][6]

Nefopam is around half the potency and slightly less effective as an analgesic compared to morphine,^[7][8] or oxycodone,^[9] but tends to produce fewer side effects, does not produce respiratory depression,^[10] and has much less abuse potential, and so is useful either as an alternative to opioids, or as an adjunctive treatment for use alongside opioid(s) or other analgesics.^[11][12]

Nefopam is also used to combat severe hiccups.^[13]

Pharmacology

The mechanism of action of nefopam is not well understood, although inhibition of serotonin, dopamine and noradrenaline reuptake is thought to be involved in its analgesic effects,^[14][15][16] and there may be other modes of action such as through histamine H3 receptors^[17] and glutamate.^[18] Recently, like its analogue orphenadrine which also has analgesic effects, nefopam has been found to act as a voltage-gated sodium channel blocker, and this may in part or fully mediate its antinociceptive effects.^[19]

Recreational Use/Overdose

Recreational use of nefopam and death from overdose have both been reported,^[20][21] although these events are less common with nefopam than with opioid analgesic drugs.^[22][23]

See also

• Orphenadrine

References

1. ^ US Patent 3830803
2. ^ Girard P, Pansart Y, Gillardin JM. Nefopam potentiates morphine antinociception in allodynia and hyperalgesia in the rat. Pharmacology, Biochemistry and Behaviour. 2004 Apr;77(4):695-703. PMID 15099914
3. ^ Alfonsi P, Adam F, Passard A, Guignard B, Sessler DI, Chauvin M (January 2004). "Nefopam, a nonsedative benzoxazocine analgesic, selectively reduces the shivering threshold in unanesthetized subjects.". Anesthesiology 100 (1): 37–43. doi:10.1097/00000542-200401000-00010. PMC 1283107. PMID 14695722. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1283107. Retrieved 2008-02-22. 
4. ^ Cohen A, Hernandez CM (1976). "Nefopam hydrochloride: new analgesic agent.". Journal of International Medical Research 4 (2): 138–43. PMID 799984. 
5. ^ Wang RI, Waite EM (July 1979). "The clinical analgesic efficacy of oral nefopam hydrochloride.". Journal of Clinical Pharmacology 19 (7): 395–402. PMID 479385. 
6. ^ Pillans PI, Woods DJ (September 1995). "Adverse reactions associated with nefopam.". New Zealand Medical Journal 108 (1008): 382–4. PMID 7566787. 
7. ^ Sunshine A, Laska E (November 1975). "Nefopam and morphine in man.". Clinical Pharmacology and Therapeutics 18 ((5 Pt 1)): 530–4. PMID 1102231. 
8. ^ Phillips G, Vickers MD (October 1979). "Nefopam in postoperative pain.". British Journal of Anaesthesia 51 (10): 961–5. doi:10.1093/bja/51.10.961. PMID 391253. 
9. ^ Tigerstedt I, Tammisto T, Leander P (December 1979). "Comparison of the analgesic dose-effect relationships of nefopam and oxycodone in postoperative pain.". Acta Anaesthesiologica Scandinavica 23 (6): 555–60. doi:10.1111/j.1399-6576.1979.tb01486.x. PMID 397711. 
10. ^ Gasser JC, Bellville JW (August 1975). "Respiratory effects of nefopam.". Clinical Pharmacology and Therapeutics 18 (2): 175–9. PMID 1097153. 
11. ^ Heel RC, Brogden RN, Pakes GE, Speight TM, Avery GS (1980). "Nefopam: a review of its pharmacological properties and therapeutic efficacy.". Drugs 19 (4): 249–67. doi:10.2165/00003495-198019040-00001. PMID 6991238. 
12. ^ Kapfer B, Alfonsi P, Guignard B, Sessler DI, Chauvin M (January 2005). "Nefopam and ketamine comparably enhance postoperative analgesia.". Anesthesia and Analgesia 100 (1): 169–74. doi:10.1213/01.ANE.0000138037.19757.ED. PMC 1283103. PMID 15616073. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1283103. Retrieved 2008-02-22. 
13. ^ Bilotta F, Rosa G. Nefopam for severe hiccups. New England Journal of Medicine. 2000 Dec 28;343(26):1973-4. PMID 11186682
14. ^ Esposito E, Romandini S, Merlo-Pich E, Mennini T, Samanin R (September 9, 1986). "Evidence of the involvement of dopamine in the analgesic effect of nefopam.". European Journal of Pharmacology 128 (3): 157–64. doi:10.1016/0014-2999(86)90762-4. PMID 3098570. 
15. ^ Marazziti D, Rotondo A, Ambrogi F, Cassano GB (1991). "Analgesia by nefopam: does it act through serotonin?". Drugs under Experimental and Clinical Research 17 (5): 259–61. PMID 1756689. 
16. ^ Fuller RW, Snoddy HD (October 1993). "Evaluation of nefopam as a monoamine uptake inhibitor in vivo in mice.". Neuropharmacology 32 (10): 995–9. doi:10.1016/0028-3908(93)90064-A. PMID 7507578. 
17. ^ Girard P, Pansart Y, Coppé MC, Verniers D, Gillardin JM (October 25, 2004). "Role of the histamine system in nefopam-induced antinociception in mice.". European Journal of Pharmacology 503 (1-3): 63–9. doi:10.1016/j.ejphar.2004.09.030. PMID 15496297. 
18. ^ Verleye M, André N, Heulard I, Gillardin JM (July 9, 2004). "Nefopam blocks voltage-sensitive sodium channels and modulates glutamatergic transmission in rodents.". Brain Research 1013 (2): 249–55. doi:10.1016/j.brainres.2004.04.035. PMID 15193535. 
19. ^ Verleye M, André N, Heulard I, Gillardin JM (July 2004). "Nefopam blocks voltage-sensitive sodium channels and modulates glutamatergic transmission in rodents". Brain Research 1013 (2): 249–55. doi:10.1016/j.brainres.2004.04.035. PMID 15193535. http://linkinghub.elsevier.com/retrieve/pii/S0006899304006444. 
20. ^ Bismuth C, Fournier PE, Bavoux E, Husson O, Lafon D. Chronic abuse of the analgesic nefopam (Acupan). (French). Journal de Toxicologie Clinique et Experimentale. 1987 Sep-Oct;7(5):343-6.
21. ^ Piercy DM, Cumming JA, Dawling S, Henry JA. Death due to overdose of nefopam. British Medical Journal (Clinical Research Edition). 1981 Dec 5;283(6305):1508-9.
22. ^ Urwin SC, Smith HS. Fatal nefopam overdose. British Journal of Anaesthesia. 1999 Sep;83(3):501-2.
23. ^ Villier C, Mallaret MP. Nefopam abuse. Annals of Pharmacotherapy. 2002 Oct;36(10):1564-6.