Several classes of drugs treat the different types and symptoms of epilepsy. The best treatment for each patient depends on the severity, frequency and symptoms of their seizures. Some patients might need more than one type of drug to control their seizures. The drug dosage(s) should be carefully monitored and adjusted to provide the best control of symptoms while minimizing the risk of dangerous side effects.
Low Blood Cell Count
Patients with epilepsy who take the medication carbamazepine should have their blood cell counts checked often when first taking the drug. Carbamazepine can decrease the number of infection-fighting white blood cells. Carbamazepine particularly affects neutrophils, white blood cells that combat dangerous bacteria. According to the Merck Manual, the drug can cause neutrophil counts to decrease to less than 1,000 per uL of blood (a condition called neutropenia).
Skin Reactions
According to the Merck Manual, most anti-convulsants can cause skin rashes. In some patients, especially Asians, a life-threatening skin disorder called Stevens-Johnson syndrome can occur in response to anti-convulsants.
Depression
The Mayo Clinic says anti-epileptic medications can cause depression and increase the likelihood of suicidal thoughts. Although the overall risk of suicide in patients taking anti-epileptic drugs is low (0.43 percent, according to the Merck Manual monograph on carbamazepine), it's double the risk of patients given a placebo (sugar pill).
Liver Malfunction
The drug valproate can cause liver malfunction. Patients using it should be tested about every three months for the first year. According to the Merck Manual, patients with epilepsy should stop taking valproate if blood levels of transaminases (enzymes that help produce amino acids) or ammonia increase twofold or more above normal.
Birth Defects
Phenytoin, carbamazepine and valproate are classified as category D drugs in pregnant women, meaning that they cross the placenta and can cause birth defects. According to the Merck Manual, pregnant women who take valproate have a slightly increased risk of neural tube defects in their babies. Other newer anti-convulsants such as felbamate, topiramate and lamotrigine are category C drugs that cause birth defects in animals, but human effects are unknown.
The Merck Manual says 4 percent of children whose mothers took anti-convulsants during pregnancy suffer from fetal antiepileptic drug syndrome--characterized by cleft lip and/or cleft palate, developmental delay, heart defects and a small head. However, the Merck Manual also says that compared to taking anti-convulsant drugs, uncontrolled maternal seizures and drinking alcohol both have a greater risk for harm to the fetus.
