Neurocritical Care

, Volume 2, Issue 3, pp 342–351 | Cite as

Magnesium neuroprotection is limited in humans with acute brain injury

  • J. Andrew McKee
  • Randall P. Brewer
  • Gary E. Macy
  • Cecil O. Borel
  • James D. Reynolds
  • David S. Warner
Review Article


Based on the results of preclinical models, magnesium sulfate (MgSO4) has gained attention as a putative neuroprotective agent. The negative results of a large-scale, randomized clinical trial using MgSO4 in acute stroke have tempered the initial enthusiasm for a neuroprotective benefit of the ion. Additional, large-scale clinical trials in stroke and other forms of brain injury are underway. This article reviews the central nervous system (CNS) physiology of Mg++, disordered Mg++ homeostasis in acute brain injury, preclinical and preliminary clinical foundations of current clinical trials, and the data regarding the CNS bio-availability of MgSO4—an important requisite for neuroprotective therapy. Although human studies have confirmed that moderate hypermagnesemia is well-tolerated and feasible, only modest elevation of cerebrospinal fluid (CSF) [Mg++] occurs. This modest increment of CSF [Mg++] in brain-injured humans occurs in the range of 10 to 19%. However, experimental evidence has yet to establish whether this modest elevation is sufficient for neuroprotection. Because of the limited CNS passage of the ion, further experimental work is needed to define the neuroprotective threshold of [Mg++] in the injured brain.

Key Words

Magnesium sulfate neuroprotective agents cerebrospinal fluid subarachnoid hemorrhage brain ischemia traumatic brain injury 


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Copyright information

© Humana Press Inc 2005

Authors and Affiliations

  • J. Andrew McKee
    • 2
  • Randall P. Brewer
    • 1
    • 2
  • Gary E. Macy
    • 1
  • Cecil O. Borel
    • 1
    • 2
  • James D. Reynolds
    • 2
  • David S. Warner
    • 2
  1. 1.Neurosciences Intensive Care UnitDuke University School of Medicine, Duke University Medical CenterDurham
  2. 2.Department of AnesthesiologyDuke University School of Medicine, Duke University Medical CenterDurham
  3. 3.c/o Laraine TuckDuke University Medical CenterDurham

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