Key takeaways
Carbamazepine (Tegretol) and phenytoin (Dilantin) are both antiepileptic medications used to treat seizures, but they have some key differences. Carbamazepine (Tegretol) is also used for trigeminal neuralgia and bipolar I disorder (Equetro brand only), while phenytoin (Dilantin) is used for grand mal seizures, temporal lobe seizures, and seizures during and after brain surgery. Carbamazepine works by blocking sodium channels in the brain, whereas phenytoin decreases abnormal signals between nerve cells. Carbamazepine comes in various forms, including pills, chewable tablets, and liquid, and can be taken up to four times a day. Phenytoin is available as capsules, chewable tablets, and liquid, and can be taken up to three times a day, with an extended-release option for once-daily dosing. Both medications require regular blood tests, but phenytoin can cause changes in appearance, like gum enlargement and unwanted hair growth. Both medications can cause serious side effects, including suicidal thoughts and severe allergic reactions, and have a risk for causing harm if used during pregnancy.
