The Spectrum of Cutaneous Adverse Drug Reactions from Systemic Drugs Caused by Delayed-Type Hypersensitivity

Drug hypersensitivity reactions (DHRs) are adverse effects of drugs that clinically resemble allergic reactions. They are called drug allergies when a definite immunological mechanism (either drug-specific antibody or T cell) has been demonstrated (23). DHRs affect more than 7% of the population (209) and 5% of hospitalized patients, and are associated with significant morbidity and mortality (58). Women are generally more often affected. The most frequent reactions are maculopapular eruptions and urticaria/angioedema. Antibiotics are most frequently implicated, mostly aminopenicillins such as amoxicillin and ampicillin. Other important classes of drugs that cause cutaneous adverse drug reactions are non-steroidal anti-inflammatory drugs (NSAIDs), contrast media and – for the more severe reactions – antiepileptics and antivirals (226).