Clinical Efficacy of Magnesium in Perioperative Pain Management: A Narrative Review

Postoperative pain is a prevalent clinical challenge that often leads to high opioid consumption, delayed hospital discharge, and associated side effects. Inadequate pain control can delay recovery and contribute to the risk of chronic postsurgical pain and opioid dependence. Magnesium, an essential cation with diverse physiological roles, has gained attention as a non-opioid adjunct for perioperative analgesia related to multimodal mechanisms of action and a favorable profile.

Pharmacologically, magnesium acts as an N-methyl-D-aspartate (NMDA) receptor antagonist and calcium channel blocker in the central nervous system, dampening excitatory neurotransmission and reducing central sensitization to pain. It also exhibits anti-inflammatory and anti-nociceptive effects and is inexpensive and easy to administer intravenously. These properties make magnesium a cost-effective and simple addition to multimodal pain management protocols. When used as a preoperative or intraoperative adjunct, magnesium has demonstrated reduced postoperative pain intensity and decreased opioid requirements across various surgical populations. Trials and meta-analyses report that patients receiving perioperative magnesium experience lower pain scores and need fewer opioids in the first 24-48 hours after surgery, translating into an opioid-sparing effect and potentially less opioid-related nausea and sedation. Importantly, magnesium has a favorable safety profile at recommended doses and generally is well-tolerated with minimal side effects apart from infrequent hypotension or mild sedation. No significant respiratory depression occurs in patients with normal renal function. The present investigation highlights magnesium-mediated analgesic mechanisms, summarizes clinical evidence for efficacy as a preoperative pain adjunct, and describes implications for improving postoperative pain outcomes and reducing opioid reliance in perioperative care.