Hypersensitivity to Aspirin and Other Non-steroidal Anti-inflammatory Drugs

Abstract

Non-steroidal anti-inflammatory drug (NSAIDs) are documented as causing the second highest number of medication-related hypersenstivity reactions and as the third highest reason for allergy consulations. The prevalence of hypersentivity to NSAIDs in the general population at large between 0.5 and 2.5%. Estimation of prevalence depends, however, on diagnostic methodology and patient characteristics, such as gender, age and the presence of comorbidity such as asthma, persistent rhinosinusitis, nasal polyps and chronic hives. Being asthmatics carries a 10-20% risk, whilst being asthmatic and having nasal polyposis carries a 30-40% risk of having NSAID-hypersensitivity. Children are less frequently affected than adults; and there is a female predilection. Classification of NSAID-hypersensitivity are based on clinical picture, whether an underlying pathology is present, and extent to which cross-reaction occurs with other members of the COX-1 inhibitor group. NSAID-exacerbated respiratory disease (NERD) refers to the combination of asthma, chronic rhinosinusitis with nasal polyposis, and acute upper and lower respiratory tract reactions to the ingestion of NSAID. Disscussion in this chapter is confined to NERD.