How to evaluate the patient after a first seizure.

The primary care physician who is approached by a patient or the parents of a patient who has had a first seizure must determine that a seizure has indeed occurred and then ascertain the type of seizure before any treatment is prescribed. While there is a variable recurrence risk after generalized tonic-clonic and partial seizures, certain types, such as absence seizures, have a high recurrence risk. Studies disagree on whether all patients with a first seizure require treatment, especially considering the side effects that can accompany anticonvulsant drugs. If the diagnosis is uncertain, waiting for a second seizure before starting treatment is usually a good idea. Electroencephalography should be done and, depending on results, followed by electrocardiography, a fasting glucose test, and/or computed tomography. If the diagnosis is certain, computed tomography or magnetic resonance imaging is useful in ruling out structural lesions as the cause of the seizure. The dosage of an anticonvulsant drug that is appropriate for the patient can then be determined by slowly increasing the dosage of one drug at a time until the patient becomes seizure-free without clinical toxicity.