Background Determination of culprit drug in drug reaction with eosinophilia and systemic symptoms (DRESS) is crucial. Skin tests have been utilised, although it remains unclear how sensitive these are. We set out to determine the value of skin tests in the assessment of drug causality in DRESS. Methods A systematic literature search was conducted for publications from 1996 onwards of skin tests (skin prick test = SPT, patch test = PT, intradermal test = IDT) performed in clearly defined DRESS cases. Outcomes of testing, drug culpability assessments and challenge tests data were extracted. Results 17 articles met inclusion criteria. In 290 DRESS patients, patch testing was most frequent [PT = 97.2% (n=282), IDT = 12.4% (n=36), SPT = 3.1% (n=9)]. Positive results were noted in 58.4% (n=160/282) of PT, 66.5% IDT and 25% SPT. When confidence of drug causality was high (n=73 of 194), testing did not correlate well with clinical suspicion: PT 37.6%; IDT 36.5% (n=19 of 52). Direct comparison of skin testing with provocation testing (n=12) showed 83.3% correlation. Positive IDTs were reported in 8 negative PT cases. Conclusion Skin tests, particularly PT and IDT, have been reported as tools for diagnosis of causal drugs in DRESS. Heterogeneity in methodology, results analysis and reporting of cohorts, makes meta-analysis to determine sensitivity and specificity of published literature impossible and highlights weaknesses in the field. We propose that international collaboration is essential to harmonise the methodology and reporting measures from hypersensitivity testing studies in larger cohorts.