A comprehensive 4-year survey of adverse drug reactions using a network-based hospital system

Spontaneous Adverse Drug Reaction Reporting Systems (ADRRS) provide early warnings or 'signals' for adverse drug reactions (ADRs). Our aim was to survey reports of ADRs made through our teaching-hospital-based pharmacovigilance system to identify the drugs most commonly associated with allergies and the types of immunological reactions reported.

Adverse drug reactions records were retrieved from our network-based electronic notification system.

Four hundred and seventy four reports of adverse drug effects were studied. 37.3% of the reactions were immune-mediated drug hypersensitivity reactions. True drug hypersensitivity reactions involving IgE-mediated drug allergies accounted for 15% of all reactions. Of the drug hypersensitivity reactions, more than half (67%) were morbilliform skin eruptions, whereas cases of urticaria accounted for 20%. Antibiotics (33% of cases) were the most commonly reported drug allergies, followed by non-steroidal anti-inflammatory drugs (13%) and anti-epileptic agents (10%).

A hospital-based ADR reporting system can generate useful data. In our study, antibiotics accounted for the majority of drug allergies, particularly anaphylactic reactions. More cases of drug allergies were owing to cephalosporin allergies than penicillins. Anti-epileptic agents caused most of the severe drug hypersensitivity syndromes.