A 16-year-old girl who recently immigrated to the United States from Bolivia presents to her primary care physician with a chief complaint of inattentiveness in school. The patient's teacher describes her as occasionally "daydreaming" for periods of time during where the patient does not respond or participate in school activities. Nothing has helped the patient change her behavior, including parent-teacher conferences or punishment. The patient has no other concerns. The only other concern that the patient's mother has is that, upon awakening, she notices that sometimes the patient's arm will jerk back and forth. The patient states she is not doing this intentionally. The patient has an unknown medical history and is currently not on any medications. She is not sexually active and does not intend to become pregnant in the near future. Her temperature is 98.6°F (37°C), blood pressure is 112/74 mmHg, pulse is 63/min, and respirations are 11/min. On physical exam, you note a young, healthy girl whose neurological exam is within normal limits. Which of the following is the most appropriate initial treatment?
Ethosuximide
Carbamazepine
Cognitive behavioral therapy
Valproic acid
Valproic acid
This patient is presenting with both absence seizures (periods of inattentiveness in school) and juvenile myoclonic epilepsy (abnormal, involuntary spasms of her upper extremity). The most appropriate treatment for these conditions is valproic acid.

Absence seizures classically present with cessation of motor activity and speech with a blank facial expression and occasionally automatisms such as flickering of the eyelids. They can be mistaken for inattentiveness in school-aged children. Juvenile myoclonic epilepsy presents with a "jerky" movement of the patient's extremity that typically occurs in the morning and begins around adolescence. The only medication that can be used to treat both absence seizures and juvenile myoclonic epilepsy is valproic acid. Valproic acid inhibits GABA transaminase, blocks thalamic T-type calcium channels, and blocks voltage-gated sodium channels. In post-pubertal female patients, it is important to counsel them on the potential teratogenic effects of this medication and also to consider alternative treatments in patients who are considering becoming pregnant or who cannot guarantee reliable birth control practices.

Kessler and McGinnis discuss the treatment of childhood absence seizures. They discuss how the treatment of choice is ethosuximide due to its favorable side effect profile. They recommend using valproic acid if there are concurrent seizure conditions.

Incorrect Answers:
Answer A: Carbamazepine would be the appropriate therapy for a partial seizure (tonic or clonic movements in addition to an absence of a post-ictal period) or for trigeminal neuralgia (sudden pain in the distribution of the trigeminal nerve). It would not address both absence seizures and juvenile myoclonic epilepsy.

Answer B: Cognitive behavioral therapy is a useful treatment that helps a patient develop coping strategies and change unhelpful patterns of thought. It could be useful if this girl was having trouble focusing in school for another reason (such as obsessive-compulsive disorder); however, it is not useful in managing seizures.

Answer C: Ethosuximide is the most appropriate initial therapy for absence seizures. In this patient, she is suffering from both absence seizures and juvenile myoclonic epilepsy which could not be treated by ethosuximide alone, in contrast to valproic acid which could treat both conditions.

Answer D: Lamotrigine is an anti-epileptic that can also be used as a mood stabilizer. It carries the potentially severe side effect of Stevens-Johnson syndrome. It is not a first-line treatment for absence seizures and juvenile myoclonic epilepsy. Stevens-Johnson syndrome will present with painful desquamation.

Bullet Summary:
Absence seizures present with periods of inattentiveness and subtle automatisms and are most appropriately treated with ethosuximide or with valproic acid if there is concurrent juvenile myoclonic epilepsy.