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Background: There is increasing use of anti‐osteoporotic agents (AOA) worldwide for prevention or management of patients with osteoporosis. However, there have been reports of severe cutaneous adverse reactions (SCAR) induced by AOA. A recent study showed weak association between HLA and strontium ranelate (SR)‐SCAR. Objective: To characterize patients with AOA‐SCAR and investigate the HLA association and utility of in vitro diagnostic methods. Methods: We enrolled 16 cases with AOA‐cutaneous adverse drug reactions (cADR), including SCAR (n = 10: 8 with Stevens–Johnson syndrome [SJS] and 2 with drug rash with eosinophilia and systemic symptoms [DRESS]) and maculopapular exanthema (MPE) (n = 6) from Taiwan and Hong Kong. We analysed the clinical characteristics, outcomes, HLA alleles and in vitro testing of AOA‐SCAR, and tolerability to alternative drugs. We further performed literature review and meta‐analysis on the HLA association of AOA‐SCAR. Results: Our data showed strontium ranelate is the most common causality of AOA‐SCAR in Asian populations. There was no cross‐hypersensitivity of SR‐SCAR with other AOA. HLA genotyping showed that SR‐SJS was most significantly associated with HLA‐A*33:03 (Pc = 5.17 × 10−3, OR: 25.97, 95% CI: 3.08–219.33). Meta‐analysis showed that HLA‐A*33:03 was associated with SR‐SJS (P = 5.01 × 10−5; sensitivity: 85.7%) in Asians. The sensitivity of lymphocyte activation test (LAT) for identifying the culprit drug of SR‐SJS was 83.3%. Conclusions: Strontium ranelate is identified as the most notorious AOA associated with SCAR. The HLA‐A*33:03 genetic allele and LAT testing may add benefits to the diagnosis of SR‐SCAR in patients whose reaction developed while taking multiple drugs. Linked Commentary: T. Shiohara. J Eur Acad Dermatol Venereol 2021; 35: 567‐568. https://doi.org/10.1111/jdv.17138. [ABSTRACT FROM AUTHOR]