Patients from Singapore have increased rates of carrying HLA-B*1502. Patients carrying HLA-B*1502 are at strongly increased risk for carbamazepine-induced Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN). Odds Ratio for SJS/TEN (Stevens Johnson Syndrome (SJS) and Toxic Epidermolytic Necrolysis (TEN)) in HLA-B*1502-positive patients relative to that in HLA-B*1502-negative patients was estimated by exact logistic regression to be 27.20 (95% CI 2.67 to 8).HLA-B*1502 positivity increases the odds of carbamazepine-induced severe adverse cutaneous drug reactions (SCDR) in Singapore children of Chinese and Malay ethnicity. Adverse drug reactions to carbamazepine occurred within 2 weeks and at low doses.(Chong, 2014).

The population mean value of carbamazepine clearance obtained in epileptic patients living in Singapore (mostly Chinese), was similar to that previously reported for patients with a very different ethnic (Caucasians and Blacks) or geographical background (South Africa, Europe and USA) (Chan,2001).

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