Nefopam, sold under the brand name Acupan among others, is a centrally acting, non-opioidpainkilling medication, that is primarily used to treat moderate to severe pain.[3]
Nefopam acts in the brain and spinal cord to relieve pain via novel mechanisms: antinociceptive effects from triple monoamine reuptake inhibition, and antihyperalgesic activity through modulation of glutamatergic transmission.[4]
Nefopam is effective for prevention of shivering during surgery or recovery from surgery.[5][6] Nefopam was significantly more effective than aspirin as an analgesic in one clinical trial,[7] although with a greater incidence of side effects such as sweating, dizziness and nausea, especially at higher doses.[8][9] The estimated relative potency of nefopam to morphine indicates that 20 mg of nefopam HCl is the approximate analgesic equal of 12 mg of morphine with comparable analgesic efficacy to morphine,[10][11][12] or oxycodone,[13] while nefopam tends to produce fewer side effects, does not produce respiratory depression,[14] and has much less abuse potential, and so is useful either as an alternative to opioid analgesics, or as an adjunctive treatment for use alongside opioids or other types of analgesics.[12][15] Nefopam is also used to treat severe hiccups.[16]
Contraindications[]
Nefopam is contraindicated in people with convulsive disorders, those that have received treatment with irreversible monoamine oxidase inhibitors such as phenelzine, tranylcypromine or isocarboxazid within the past 30 days and those with myocardial infarction pain, mostly due to a lack of safety data in these conditions.[17]
Side effects[]
Common side effects include nausea, nervousness, dry mouth, light-headedness and urinary retention.[17] Less common side effects include vomiting, blurred vision, drowsiness, sweating, insomnia, headache, confusion, hallucinations, tachycardia, aggravation of angina and rarely a temporary and benign pink discolouration of the skin or erythema multiforme.[17]
Overdose[]
Overdose and death have been reported with nefopam.[18] Overdose usually manifests with convulsions, hallucinations, tachycardia, and hyperdynamic circulation.[17] Treatment is usually supportive, managing cardiovascular complications with beta blockers and limiting absorption with activated charcoal.[17]
Interactions[]
It has additive anticholinergic and sympathomimetic effects with other agents with these properties.[17] Its use should be avoided in people receiving some types of antidepressants (tricyclic antidepressants or monoamine oxidase inhibitors) as there is the potential for serotonin syndrome or hypertensive crises to result.[17]
The mechanism of action of nefopam and its analgesic effects are not well understood, although inhibition of the reuptake of serotonin, norepinephrine, and to a lesser extent dopamine (that is, acting as an SNDRI) is thought to be involved.[21][4] It also reduces glutamate signaling via modulating sodium and calcium channels.[22][4]
Pharmacokinetics[]
The absolute bioavailability of nefopam is low.[1] It is reported to achieve therapeutic plasma concentrations between 49 and 183 nM.[20] The drug is approximately 73% protein-bound across a plasma range of 7 to 226 ng/mL (28–892 nM).[1] The metabolism of nefopam is hepatic, by N-demethylation and via other routes.[1] Its terminal half-life is 3 to 8 hours, while that of its active metabolite, desmethylnefopam, is 10 to 15 hours.[1] It is eliminated mostly in urine, and to a lesser extent in feces.[1]
Chemistry[]
Nefopam is a cyclizedanalogue of orphenadrine, diphenhydramine, and tofenacin, with each of these compounds different from one another only by the presence of one or two carbons.[23][24][25] The ring system of nefopam is a system.[23][26]
Society and culture[]
Recreational use[]
Recreational use of nefopam has rarely been reported,[18] and is far less common than with opioid analgesics.[27]
Names[]
In the 1960s, when it was first developed, it had the generic name fenazoxine.[22]
See also[]
Troparil
References[]
^ Jump up to: abcdefghijklmSanga M, Banach J, Ledvina A, Modi NB, Mittur A (November 2016). "Pharmacokinetics, metabolism, and excretion of nefopam, a dual reuptake inhibitor in healthy male volunteers". Xenobiotica; the Fate of Foreign Compounds in Biological Systems. 46 (11): 1001–16. doi:10.3109/00498254.2015.1136989. PMID26796604. S2CID34603935.
^Kang P, Park SK, Yoo S, Hur M, Kim WH, Kim JT, Bahk JH (January 2019). "Comparative effectiveness of pharmacologic interventions to prevent shivering after surgery: a network meta-analysis". Minerva Anestesiologica. 85 (1): 60–70. doi:10.23736/S0375-9393.18.12813-6. PMID30226340.
^Cohen A, Hernandez CM (1976). "Nefopam hydrochloride: new analgesic agent". The Journal of International Medical Research. 4 (2): 138–43. doi:10.1177/030006057600400211. PMID799984. S2CID41618926.
^Wang RI, Waite EM (July 1979). "The clinical analgesic efficacy of oral nefopam hydrochloride". Journal of Clinical Pharmacology. 19 (7): 395–402. doi:10.1002/j.1552-4604.1979.tb02498.x. PMID479385. S2CID25877487.
^Pillans PI, Woods DJ (September 1995). "Adverse reactions associated with nefopam". The New Zealand Medical Journal. 108 (1008): 382–4. PMID7566787.
^Sunshine A, Laska E (November 1975). "Nefopam and morphine in man". Clinical Pharmacology and Therapeutics. 18 (5 Pt 1): 530–4. doi:10.1002/cpt1975185part1530. PMID1102231. S2CID19051105.
^ Jump up to: abHeel RC, Brogden RN, Pakes GE, Speight TM, Avery GS (April 1980). "Nefopam: a review of its pharmacological properties and therapeutic efficacy". Drugs. 19 (4): 249–67. doi:10.2165/00003495-198019040-00001. PMID6991238. S2CID24713213.
^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. PMID397711. S2CID40976610.
^Gasser JC, Bellville JW (August 1975). "Respiratory effects of nefopam". Clinical Pharmacology and Therapeutics. 18 (2): 175–9. doi:10.1002/cpt1975182175. PMID1097153. S2CID22220503.
^Bilotta F, Rosa G (December 2000). "Nefopam for severe hiccups". The New England Journal of Medicine. 343 (26): 1973–4. doi:10.1056/nejm200012283432619. PMID11186682.
^ Jump up to: abBismuth C, Fournier PE, Bavoux E, Husson O, Lafon D (September 1987). "[Chronic abuse of the analgesic nefopam (Acupan)]". Journal de Toxicologie Clinique et Expérimentale (in French). 7 (5): 343–6. PMID3448182.
^Roth, BL; Driscol, J. "PDSP Ki Database". Psychoactive Drug Screening Program (PDSP). University of North Carolina at Chapel Hill and the United States National Institute of Mental Health. Retrieved 14 August 2017.
^Bausch & Lomb (NZ) Ltd (17 May 2017). "NEW ZEALAND DATA SHEET ACUPAN(TM)"(PDF). Medsafe. New Zealand The Ministry of Health. Retrieved 4 September 2017.