Neuropathic pain (NP), arising from dysfunction in the neurological system, poses a significant challenge in pain management due to its intricate origin and unpredictable response to conventional treatments. Electroanalgesia, a collection of techniques such as transcutaneous electric nerve stimulation (TENS), peripheral electrical nerve stimulation (PENS), spinal cord stimulation (SCS), deep brain stimulation (DBS), and electroacupuncture (EA), presents a potential alternative or complementary approach. This review brings together evidence from 56 studies to evaluate the effectiveness and safety of electroanalgesia in chronic NP. It discusses the mechanisms underlying NP, the indications for electroanalgesia, and the techniques utilized, emphasizing the diverse applications and potential benefits. However, despite its potential uses, electroanalgesia has its limitations, including variable effectiveness and potential adverse effects. Furthermore, the review recognizes the limitations of the methodology and the need for further research to refine treatment protocols and enhance the understanding of electroanalgesia\'s role in comprehensive pain management strategies.

The objective was to qualitatively synthesize all reported cases of complications, adverse effects, side effects, or harms arising from the use of scrambler therapy (ST).
A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. The PubMed, Embase, Scopus, Web of Science, United States National Library of Medicine clinical trials registry, and Cochrane Central Register of Controlled Trials databases were searched from database inception to December 10, 2021. Case reports/series, abstracts, retrospective studies, and prospective studies (e.g., open-label trials, randomized controlled trials) pertaining to ST and any description of a complication, adverse effect, side effect, or harm were screened. The search protocol was developed a priori and registered via the International Prospective Register of Systematic Reviews (PROSPERO ID: CRD42021291838).
A total of six RCTs, 19 prospective open-label trials, and 11 case series / case reports met the inclusion criteria, comprising 1,152 total patients. Two patients experienced contact dermatitis, and one patient reported minor ecchymosis that resolved without intervention. This yielded a composite complication rate of 0.26% (3/1,152). There were zero reported serious adverse events.
When used in accordance with the treatment protocols described by the United States Food and Drug Administration and device manual, ST is associated with a reported composite complication rate that is orders of magnitude lower than those of invasive neuromodulation devices. ST neuromodulation is a safe alternative for patients who cannot undergo invasive neuromodulation device implantation because of either risk or preference.