American Board of Internal Medicine (ABIM) Certification Practice Exam

Which antiepileptic drug is preferred for patients with metastatic brain tumors experiencing seizures?

1. Phenytoin

2. Valproic acid

3. Carbamazepine

4. Phenobarbital

The correct answer is: Valproic acid

Valproic acid is preferred for patients with metastatic brain tumors experiencing seizures due to its efficacy in managing seizure types commonly seen in these patients, as well as its favorable side effect profile. Unlike other antiepileptic drugs, valproic acid has potential benefits in patients with brain tumors because it not only effectively controls various seizure types but also may have neuroprotective properties and can possibly inhibit tumor growth. Moreover, it does not induce liver enzymes to the same extent as phenytoin and carbamazepine, making it a safer choice in this population that may already have compromised liver function due to malignancy or related treatments. The choice of valproic acid over other antiepileptic medications aligns with current clinical practice guidelines, recognizing its effectiveness in reducing seizure frequency while minimizing the risk of drug interactions, which could be critical in patients receiving concurrent cancer therapies.