BACKGROUND: Preclinical studies have shown that lithium modifies pathological 
cascades implicated in certain neurodegenerative disorders, such as Alzheimer's 
disease (AD), Huntigton`s disease (HD), multiple system atrophy (MSA) and 
amyotrophic lateral sclerosis (ALS). A critical question is whether these 
pharmacodynamic properties of lithium translate into neurodegenerative diseases 
modifying effects in human subjects.
METHODS: We reviewed all English controlled clinical trials published in PubMed, 
PsycINFO, Embase, SCOPUS, ISI-Web with the use of lithium for the treatment of 
neurodegenerative disorders between July 2004 and July 2014.
RESULTS: Lithium showed evidence for positive effects on cognitive functions and 
biomarkers in amnestic mild cognitive impairment (aMCI, 1 study) and AD (2 
studies), even with doses lower than those used for mood stabilisation. Studies 
of Li in HD, MSA and CSI did not show benefits of lithium. However, due to 
methodological limitations and small sample size, these studies may be 
inconclusive. Studies in ALS showed consistently negative results and presented 
evidence against the use of lithium for the treatment of this disease.
CONCLUSION: In absence of disease modifying treatments for any neurodegenerative 
disorders, the fact that at least 3 studies supported the effect of lithium in 
aMCI/AD is noteworthy. Future studies should focus on defining the dose range 
necessary for neuroprotective effects to occur.