• Glucose abnormalities and hyponatremia are the two laboratory findings most frequently associated with triggering first-time seizures in adult patients.

• Always check an HCG in women who present with their first seizure, as this may reveal the source (i.e. eclampsia) and/or may affect testing, disposition, and initiation of an anti-epileptic drug (AED).

• Drug abuse screens should be considered in patients with their first seizure, but no prospective studies have demonstrated benefit from routine use.

References

• Turnbull, et al. "Utility of laboratory studies in the ED patient with a new onset seizure."  Ann Emerg Med. 1990; 19: 373-77.
• Eisner, et al. "Efficacy of a standard seizure workup in the ED." Ann Emerg Med. 1986; 15: 33-9.