Previous studies have shown that carbamazepine-induced Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) patients is associated with the HLA-B*1502 allele. Screening for HLA-B*1502 before using carbamazepine can prevent SJS/TEN particularly in populations with high frequency of the allele. The objective of this paper was to describe how the UKM Medical Centre, Malaysia was able to set up a cost effective screening of HLA-B*1502 for patients taking carbamazepine. The cost of in-house HLA-B⁄1502 screening was less than those commercially available, and was sensitive and specific.