Prolonged seizures produce central nervous system damage. Physiologic consequences of status epilepticus may exacerbate this damage or may mislead the physician into making inappropriate therapeutic decisions. Status results in an elevation of body temperature, an increase in the peripheral white cell count, and often a transient pleocytosis in the spinal fluid. A marked metabolic acidosis occurs routinely. Prominent elevations in plasma hormonal concentrations occur as well. Epinephrine levels are in the arrhythmogenic range and could play a role in sudden death. Transient but marked pressure responses occur in the systemic and pulmonary circulations. Pulmonary edema may result from these pressure transients.