Avoiding severe drug hypersensitivity reactions: a case for HLA genotyping for at‐risk patients

Jana Stojanova, Richard O Day and Graeme Suthers
Med J Aust || doi: 10.5694/mja2.51937
Published online: 15 May 2023

Several human leucocyte antigen alleles are associated with severe drug hypersensitivity reactions, and Asian Australians have a relatively high risk of carrying such alleles

Prescribing decisions are always personalised, and may consider a patient's age, gender, health conditions and concurrent medications. Pharmacogenetics has the potential to provide additional information to inform these decisions. In a recent MJA article, White and colleagues put forward a call for a sustainable evidence‐based pharmacogenomic screening program for Australia, highlighting DPYD genotyping before fluoropyrimidine chemotherapy as an urgent need.1 DPYD, TPMT and UGT1A1 genotyping are performed to avoid severe toxicities associated with drug over‐exposure in the setting of antineoplastic therapy. With the exception of TPMT, these tests are not typically requested in the community setting. The abbreviations of these and other metabolic enzymes used throughout this article are defined in Box 1.

  • 1 St Vincent's Hospital Sydney, Sydney, NSW
  • 2 St Vincent's Clinical School, UNSW, Sydney, NSW
  • 3 Sonic Healthcare Australia Pathology, Sydney, NSW



We thank Jane Carland (St Vincent's Hospital Sydney) and Sophie Stocker (the University of Sydney) for providing valuable suggestions and feedback on the manuscript.

Competing interests:

Graeme Suthers is Director of Genetics, Sonic Health Australia, a provider of HLA genotyping tests.

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