The beneficial cardiovascular effect of allopurinol may be related to several potential mechanisms including: (1) allopurinol associated attenuation of intercellular adhesion molecule-1 levels noted in patients after a recent stroke [27]; (2) improvement in endothelial function and reduction of oxidative stress with allopurinol [28–33]; and (3) reduction in glycosylated hemoglobin (HbA1C) with high-doses of allopurinol [33]. This evidence concerns the gene ICAM1 and Stroke.