Summary
Definition
History and exam
Key diagnostic factors
- history of drug exposure
- skin lesions
- variable skin reactions within 5 to 15 minutes of drug exposure
- variable skin reactions within a few hours of drug exposure
- variable skin reactions within 2 weeks of drug exposure
- variable skin reactions within months to years of drug exposure
- previous exposure and reaction to drug
Other diagnostic factors
- pruritus
- associated noncutaneous features
- pain
Risk factors
- virus infections
- HIV infection
- HLA-B*5701 polymorphism
- HLA-B*1502 polymorphism
- HLA-B*5801 polymorphism
- female sex
Diagnostic tests
Tests to consider
- blood (whole blood, plasma, serum) drug concentration
- serum tryptase concentration (anaphylaxis)
- complement pathway assay
- histology of lesion biopsy
- CBC and differential
- antihistone antibodies to single-stranded DNA (lupus-like syndrome)
- skin tests (prick tests, intradermal tests, patch tests)
Emerging tests
- drug-specific IgE
- basophil activation test
- lymphocyte proliferation assay (LPA/LTT)
- enzyme-linked immunospot assay (ELISPOT test)
Treatment algorithm
serious cutaneous adverse reactions
nonserious cutaneous adverse reactions
following acute episode
Contributors
Authors
Michael Ardern-Jones, BSc, MBBS, DPhil, FRCP
Associate Professor
Consultant Dermatologist
Faculty of Medicine
University of Southampton
Southampton
UK
Disclosures
MA-J declares that he has no competing interests.
Acknowledgements
Dr Michael Ardern-Jones would like to gratefully acknowledge Dr Wei Yann Haw, Dr Anne Holbrook, Dr Hermenio Lima, and Dr Jeffrey K. Aronson, the previous contributors to this topic.
Disclosures
WYH, AH and HL declare that they have no competing interests. JKA is editor of Meyler's Side Effects of Drugs and its annual companion volumes, the Side Effects of Drugs Annuals.
Peer reviewers
Shahbaz A. Janjua, MD
Specialist Dermatologist
Ayza Skin & Research Center
Lalamusa
Pakistan
Disclosures
SAJ declares that he has no competing interests.
Craig K. Svensson, Pharm.D, PhD
Dean
College of Pharmacy, Nursing, and Health Sciences
Purdue University
West Lafayette
IN
Disclosures
CKS declares that he has no competing interests.
Differentials
- Systemic lupus erythematosus
- Autoimmune blistering disorders
- Staphylococcal scalded skin syndrome
More DifferentialsGuidelines
- Drug allergy: a 2022 practice parameter
- Emergency treatment of anaphylactic reactions
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