CYP3A4 and neuroleptic malignant syndrome: There are many case reports of NMS associated with quetiapine.7 In most of the cases reported, the NMS is caused either after a coadministration of quetiapine with other medication or when other medical conditions have been involved.8 A possible mechanism could be that the hepatic enzyme cytochrome P450 3A4, which played a major role in the metabolism of quetiapine, could be induced, and the blood concentration of quetiapine decreased.