Severe preeclampsia is a pathophysiological disorder specific to pregnancy and characterized by vasoconstriction and hypercoagulability. Eclampsia (convulsion associated with preeclampsia) and hemolysis, elevated liver enzymes, and low platelet count associated with preeclampsia (HELLP syndrome) are serious complications in patients with severe preeclampsia. They are thought to be characterized by generalized vasoconstriction and reduction in blood flow to various organs that may be explained by increased sensitivity of the vascular smooth muscles and increased vasopressors. Liver involvement in eclampsia and preeclampsia is referred to as HELLP syndrome, and epigastric and right upper quadrant pain is often a symptom of severe preeclampsia and may be indicative of imminent convulsions. In addition, marked dilatation of the stomach and the colon is often demonstrated in these patients. These phenomena result from the hyperactivity of the sympathetic nervous system but are not caused by the hyperactivity of the parasympathetic nervous system. The authors experienced two cases of eclamptic seizures after the administration of an anticholinergic (scopolamine butylbromide) in patients with severe preeclampsia complicated by HELLP syndrome. Anticholinergics, blocking agents of the parasympathetic nervous system, can enhance the hyperactivity of the sympathetic nervous system; therefore, vasospasms of the vessels may be easily aggravated, and eclamptic seizures may be induced in patients with severe preeclampsia, especially in those complicated by HELLP syndrome. The administration of anticholinergics should be avoided in patients with severe preeclampsia, especially when there is epigastralgia.