Korean J Pain 2014; 27(2): 103-111
Published online May 1, 2014 https://doi.org/10.3344/kjp.2014.27.2.103
Copyright © The Korean Pain Society.
Kyung Hoon Kim, and Salahadin Abdi**
Department of Anesthesia and Pain Medicine, School of Medicine, Pusan National University, Yangsan, Korea.
*Department of Pain Medicine, Division of Anesthesiology and Critical Care, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
Correspondence to: Salahadin Abdi. Department of Pain Medicine, Division of Anesthesiology and Critical Care, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd. Unit 0409 Houston, TX 77030, USA. Tel: +1-713-792-6070, Fax: +1-713-745-5063, SAbdi@mdanderson.org
Received: September 16, 2013; Revised: December 4, 2013; Accepted: December 5, 2013
This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Nefopam (NFP) is a non-opioid, non-steroidal, centrally acting analgesic drug that is derivative of the non-sedative benzoxazocine, developed and known in 1960s as fenazocine. Although the mechanisms of analgesic action of NFP are not well understood, they are similar to those of triple neurotransmitter (serotonin, norepinephrine, and dopamine) reuptake inhibitors and anticonvulsants. It has been used mainly as an analgesic drug for nociceptive pain, as well as a treatment for the prevention of postoperative shivering and hiccups. Based on NFP's mechanisms of analgesic action, it is more suitable for the treatment of neuropathic pain. Intravenous administration of NFP should be given in single doses of 20 mg slowly over 15-20 min or with continuous infusion of 60-120 mg/d to minimize adverse effects, such as nausea, cold sweating, dizziness, tachycardia, or drowsiness. The usual dose of oral administration is three to six times per day totaling 90-180 mg. The ceiling effect of its analgesia is uncertain depending on the mechanism of pain relief. In conclusion, the recently discovered dual analgesic mechanisms of action, namely, a) descending pain modulation by triple neurotransmitter reuptake inhibition similar to antidepressants, and b) inhibition of long-term potentiation mediated by NMDA from the inhibition of calcium influx like gabapentinoid anticonvulsants or blockade of voltage-sensitive sodium channels like carbamazepine, enable NFP to be used as a therapeutic agent to treat neuropathic pain.
Keywords: adverse drug reactions, molecular mechanisms of pharmacological action, nefopam, neuropathic pain, nonopioid analgesics