Intravenous Magnesium for the Management of Chronic Pain:An Updated Review of the Literature

BACKGROUND: Available therapeutic options are currently limited by their modest efficacy. As a result, novel pharmacotherapeutic treatments with different mechanisms have recently attracted empirical attention. Magnesium, a divalent cation, is postulated to provide analgesic and anti-nociceptive effect through its action at the N-methyl-D-aspartate (NMDA) receptor. OBJECTIVE: Considering the evidence surrounding magnesium's potential as a therapeutic modality for chronic pain, we conducted a narrative review on the evidence of magnesium's therapeutic effects in chronic pain. METHODS: A review of the PubMed, and Google scholar databases was undertaken in May 2022 to identify completed studies that investigated the effectiveness of magnesium in the treatment of chronic pain from database inception to May 2022. RESULTS: A total of 33 studies were included in the narrative review, out of which 26 were randomized controlled trials. Findings on available studies suggest that intravenous infusion of magnesium is an emerging and promising option that may alleviate pain in some clinical populations. Our narrative synthesis showed that evidence for intravenous magnesium is currently equivocal for a variety of chronic pain syndrome. Findings indicate that evidence for efficacy is poor or equivocal for: CRPS, neuropathic pain, chronic low back pain, and migraine prophylaxis. However, there is good evidence supporting the efficacy of intravenous magnesium for treating renal colic pain and pelvic pain related to endometriosis. CONCLUSION: Magnesium may be a promising pharmacologic solution for chronic pain. Future investigation is warranted on elucidating the neurobiological mechanisms of magnesium in attenuating pain signaling pathways.