Calcium (Ca(2+)) and magnesium (Mg(2+)) influence the molecular pathways of ischemic neuronal death. The authors evaluated the impact of admission serum Ca(2+) and Mg(2+) levels, on incident stroke severity and discharge functional outcome. After adjusting for covariates, higher admission Ca(2+) was significantly associated with lesser stroke severity and better discharge functional outcome. Admission Mg(2+) was not an independent clinical outcome prognosticator.