FDA approves warning for carbamazepine

WASHINGTON, Dec. 12 (UPI) -- The U.S. manufacturers of drugs containing carbamazepine have agreed to warn Asian patients to get a genetic blood test before using the medication.

The U.S. Food and Drug Administration said the warning will be added to the labeling of the drug so new patients of Asian ancestry can determine if they have a significantly increased risk of developing a rare, but serious, skin reaction.

Carbamazepine is used for treatment of epilepsy, bipolar disorder, and neuropathic pain. It is sold under the brand names Carbatrol, Equetro and Tegretol.

"When being considered for treatment with carbamazepine, genetically high-risk patients can be given a test that will help their healthcare providers make personalized drug treatment decisions and help avoid potentially serious skin reactions," said Dr. Janet Woodcock, the FDA's deputy commissioner for scientific and medical programs.

The risk of such skin reactions is about 1 to 6 per 10,000 patients in countries with mainly white populations. However, the risk is estimated to be about 10 times higher in some Asian nations.

A spokeswoman for Novartis, which makes Tegretol, said the warning is meant for new patients and if patients have been taking the drug for more than a few months and haven't had a reaction, they are unlikely to experience these reactions regardless of ancrestry or genetic test results.

The FDA said the new recommendation will added to drug's the boxed warning section.