Magnesium sulfate is considered a neuroprotective drug and has been studied in various applications. Recently, it has drawn the attention of anesthesiologists, resulting in numerous publications about its role in anesthesiology. Magnesium sulfate is suggested to exert its neuroprotective effect by preventing excitotoxicity. in the clinical setting, intraoperative magnesium sulfate attenuated POCD. Furthermore, postoperative emergence agitation was significantly reduced in pediatric patients who received intraoperative magnesium sulfate during adenotonsillectomy. The aim of this study The aim of this work is to compare the protective effect of intraoperative dexmedetomidine with magnesium sulfate against developing POCD and to study their effect on serum level of CRP; the marker of neuronal degeneration.