Pharmacogenomics of Allopurinol and Sulfamethoxazole/Trimethoprim: Case Series and Review of the Literature

Severe cutaneous adverse drug reactions (SCAR) such as the Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) and drug rash with eosinophilia and systemic symptoms/drug-induced hypersensitivity syndrome (DIHS) can be induced by a plethora of medications. The field of pharmacogenomics aims to prevent severe adverse drug reactions by using our knowledge of the inherited or acquired genetic risk of drug metabolizing enzymes, drug targets, or the human leukocyte antigen (HLA) genotype. Dermatologists are experts in the diagnosis and management of severe cutaneous adverse drug reactions (SCAR) in both the inpatient and outpatient setting. However, most dermatologists in the US have not focused on the prevention of SCAR. Therefore, this paper presents a case series and review of the literature highlighting salient examples of how dermatologists can apply pharmacogenomics in the diagnosis and especially in the prevention of SCAR induced by allopurinol and sulfamethoxazole/trimethoprim, two commonly prescribed medications.

Automated summary

Pharmacogenomics plays a crucial role in preventing severe cutaneous adverse drug reactions. Dermatologists are experts in diagnosing and managing SCAR, but often overlook prevention strategies. Utilizing pharmacogenomics for preventing SCAR can be particularly beneficial in the context of commonly prescribed medications.