Patients with one or two copies of the HLA-B*15:02:01 allele may have an increased risk of Severe Cutaneous Adverse Reactions when treated with carbamazepine as compared to patients with no HLA-B*15:02:01 alleles or negative for the HLA-B*15:02:01 test. However, conflicting evidence has been reported. Other genetic and clinical factors may also influence risk of carbamazepine-induced adverse reactions.