Carbamazepine

• You may know this drug as: Carbatrol®, Epitol®, Equetro®, Tegretol®, Tegretol XR®
• Why it's commonly used: This anti-convulsant is used to treat epilepsy, pain, and certain psychiatric conditions, including bipolar disorder and schizophrenia. It's also sometimes used to treat attention-deficit/hyperactivity disorder (ADHD).
• Side effects: Potentially life-threatening dermatological conditions, which can include fever, body aches, a rash, blisters on mucous membranes, and small areas or large areas of peeling skin
• What you can do: Knowing your genetic risk of side effects allows you and your doctor to choose the right drugs for you, and opt for alternatives if needed.
• Did you know? Serious skin reactions are estimated to occur in 6 out of all 10,000 new carbamazepine users. This side effect is of special concern for people of Asian descent, especially those of Chinese ancestry.

The genetic risk variant related to carbamazepine side effects occurs most often in people of Asian ancestry, which is why the U.S. Food and Drug Administration recommends genetic screening for this variant for people of Asian ancestry before beginning treatment with carbamazepine. Here is how often the risk variant appears in various Asian populations, according to FDA statistics:

• Ten to 15 percent or more of patients may carry the variant in parts of China, Thailand, Malaysia, Indonesia, the Philippines, and Taiwan.
• South Asians, including Indians, appear to have intermediate rates of this variant, averaging about two to four percent of patients, but rates are higher in some sub-groups.
• HLA-B*1502 appears to be present at low rates (less than one percent of the population) in Japan and Korea.