FDA MedWatch - Carbamazepine - Dangerous Or Fatal Skin Reactions Significantly More Common In Patients With A Particular Human LeukocyteAntigen (HLA) Allele

 

Those who have been taking carbamazepine (Tegretol) for months without a skin reaction are unlikely to develop these problems, even if they have the designated heritage.

Those who have the appropriate ancestry and have not taken carbamazepine (Tegretol) should be screened before beginning the medication.

 

FDA informed healthcare professionals that dangerous or even fatal skin reactions (Stevens Johnson syndrome and toxic epidermal necrolysis), that can be caused by carbamazepine therapy, are significantly more common in patients with a particular human leukocyte antigen (HLA) allele, HLA-B*1502. This allele occurs almost exclusively in patients with ancestry across broad areas of Asia, including South Asian Indians. Patients with ancestry from areas in which HLA-B*1502 is present should be screened for the HLA-B*1502 allele before starting treatment with carbamazepine. If these individuals test positive, carbamazepine should not be started unless the expected benefit clearly outweighs the increased risk of serious skin reactions. Patients who have been taking carbamazepine for more than a few months without developing skin reactions are at low risk of these events ever developing from carbamazepine. This is true for patients of any ethnicity or genotype, including patients positive for HLA-B*1502.

Posted 1-10-08