Diagnosing and managing patients with drug hypersensitivity

ABSTRACT

Introduction: Diagnosing and managing drug hypersensitivity is challenging because there are no clear limits between different types of drug reactions. Distinguishing between type A (predictable) and type B (hypersensitivity) reactions when a drug is introduced on the market is not easy. When many people use a drug, adverse reactions can occur, conditioned by diverse genetic profiles, viral infections or concomitant therapy. Occasionally the only tool clinicians have on which to base the diagnosis is the clinical history. Skins tests or in vitro tests sometimes have low sensitivity or are unavailable, and drug provocation tests may be dangerous or strictly forbidden in case of severe cutaneous reactions.

Areas covered: This paper reviews the diagnosis and management of the two main types of immunological reactions: IgE-mediated immediate drug hypersensitivity reactions (IDHRs) and non-immediate drug hypersensitivity reactions (NIDHRs).

Expert commentary: Although Europe and the United States use different diagnostic methods, patients with history of drug hypersensitivity must avoid the suspicious drug, and clinicians must assess tolerance to safe alternatives under medical surveillance. Sometimes desensitization may be required. There is a consensus about the need to perform genetic testing for specific drugs and give patients proper documentation to prevent future exposure to culprit drugs.

KEYWORDS:

• Cross-reactivity
• diagnosis
• drug hypersensitivity
• in vitro tests
• management
• skin tests

Acknowledgements

The authors wish to thank Meggan Harris for helping with the translation.

Declaration of interest

Both I Doña and J Fernandez belong to the Network Asthma, Adverse and Allergic Reactions. (ARADYAL) supported by Institute of Health ‘Carlos III’ of the Ministry of Economy and Competitiveness. I Dona holds a ‘Juan Rodes’ research contract (JR15/00036) supported by Institute of Health ‘Carlos III’ of the Ministry of Economy and Competitiveness (grants cofounded by European Social Fund ESF). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was funded by a grant from the Institute of Health ‘Carlos III’ of the Ministry of Economy and Competitiveness, grant number RD16/06/32.