Lithium is a potent inhibitor of GSK3β activity (Engel et al., 2006; Tan et al., 2010; Forlenza et al., 2014; Kerr et al., 2018; Hampel et al., 2019; Li et al., 2020) and, in animal models of AD, chronic lithium treatment was associated with reduced hyperphosphorylation of Tau and Aβ accumulation (Su et al., 2004; Noble et al., 2005; Engel et al., 2006; Forlenza et al., 2014). This evidence concerns the gene MAPT and Alzheimer disease.