[The analgesic effect of intravenous lidocaine in the treatment of chronic pain: a literature review]

Background: Pain is a public health problem, greatly impairing quality of life. Almost 80% of patients with chronic pain reported that their pain interferes with activities of daily living, and two thirds reported that the pain causes negative impact on their personal relationships. The physical and functional disability, whether temporary or permanent, compromises the professional activity and causes work absenteeism, increasing costs of health systems.

Objectives: The aim of this review is to analyze, based on the literature, the analgesic effect of lidocaine administered intravenously for the treatment of chronic pain and to evaluate the reduction of pain intensity in patients with chronic pain, focusing on musculoskeletal and neuropathic etiology.

Methodology: The method used was a review of the literature, consisting in searching the scientific literature on the efficacy of intravenous lidocaine infusion in the treatment of patients with chronic pain.

Content: Of the 19 studies reviewed, 12 had results that confirm the analgesic effect of intravenous lidocaine in patients with chronic pain. Most authors used doses of 5mg/kg infused for 30minutes or more, producing significant analgesia with variable duration (minutes to weeks).

Conclusions: Based on the literature review, it is not possible to uniformly specify the most effective and safe dose of lidocaine administered intravenously for the treatment of neuropathic or musculoskeletal pain. As for effectiveness, the intravenous infusion of lidocaine as an alternative for the treatment of chronic pain of various etiologies seems very promising, but further studies need to be conducted.