Effectiveness of mexiletine for treatment of neuropathic pain
Asif A, Malik MF, Lundberg K, Tarabishy A, Hanna J. Effectiveness of mexiletine for treatment of neuropathic pain. Regional Anesthesia and Pain Medicine 2017; 42(6).
Regional Anesthesia and Pain Medicine
Introduction Neuropathic pain, generated by disorders of the peripheral and central nervous system, can be particularly severe and disabling. Prevalence estimates indicate that upto 5% of the population in the developed world suffer from neuropathic pain, that can be disabling, thus remains a major clinical problem (1). Many patients with chronic pain do not obtain adequate relief from existing treatment. Moreover, even when prior research reports positive outcomes, the long-term benefits of such treatment have not been demonstrated. Efforts to develop treatments that provide improved outcomes are therefore a priority for pain research (1,2). Materials and methods (NA for case report) The primary outcome of our IRB approved retrospective chart review study was defined as partial or complete resolution of various neuropathic pain syndromes after receiving mexiletine for neuralgia, which was determined by the timing and evaluation at their next appointment for symptoms, accompanied by improvement in overall function, related to neuralgia. Results/Case report Our findings suggest that mexiletine can be a safe and effective adjuvant in the management of chronic pain syndrome and possibly other pain syndromes of various origins. However, treatment must be individualized for each patient based on efficacy, side-effect profile and drug accessibility, including cost. Further studies are required to examine head-to-head comparisons among analgesics, combinations of analgesics, long-term outcomes, and treatment of neuropathic pain. Discussion Recommendations for treatment are based on degree of evidence of analgesic efficacy, safety, ease of use and cost-effectiveness (1). Analgesic agents recommended for first-line treatments are certain antidepressants (tricyclics) and anticonvulsants (gabapentin and pregabalin) (2). Secondline treatments recommended are serotonin noradrenaline reuptake inhibitors and topical lidocaine (2). Tramadol and controlled-release opioid analgesics are recommended as third-line treatments for moderate to severe pain. Recommended fourth-line treatments include cannabinoids, methadone and anticonvulsants with lesser evidence of efficacy, such as lamotrigine, topiramate and valproic acid (2). However, our IRB approved retrospective chart review indicates mexiletine as an adjuvant with improved analgesic response profile on various neuropathic pain syndromes for prolonged analgesia in patients with neuralgia.