379 Adverse Drug Reactions to Anti-asthmatics in Patients with Bronchial Asthma

BACKGROUND: The number of self-reported adverse drug reactions (ADRs) has been rapidly increased with the active pharmacovigilance activities in Korea. However, there has been few data on ADRs to anti-asthmatics in Korea. This study was conducted to investigate the clinical characteristics of ADRs to anti-asthmatics in adult patients with bronchial asthma. METHODS: ADRs to anti-asthmatics reported to Regional Pharmacovigilance Center of Inha University Hospital by 2 physicians were collected from January 2011 to April 2011. Causality assessment of adverse events was performed by using WHO-UMC criteria and Naranjo's probability scale. Clinical information was additionally collected from electronic medical records. RESULTS: Twenty five ADRs to anti-asthmatics were reported in 19 (male 5, female 14) out of 228 patients with asthma. The most common offending anti-asthmatics were inhaled glucocorticoids combined with inhaled long-acting beta agonist (LABA) (12 of 19 subjects, 63.2%), theobromine (10.5%), oral LABA (10.5%), doxofylline (5.3%), acetylcysteine (5.3%), and montelukast (5.3%). Severity of ADRs was mild in most patients (13 of 19, 68.5%), and no severe ADR was detected. By frequency, oral LABA was the commonest drug associated with ADRs (2 in 17 prescription, 11.8%). ADR frequency was not different according to asthma control status. But ADRs to simultaneously prescribed drugs were more frequently detected in patients with combined upper airway diseases (ADRs to antihistamines) or patients with combined infection (ADRs to anti-infective drugs, mucolytics, oral LABA, or to SABA), or older patients with asthma. CONCLUSIONS: Although the severity is usually mild, ADRs are relatively common in patients with bronchial asthma. Physician should monitor ADRs to anti-asthmatics or related drugs in patients with asthma, especially in older patients or in patients with multiple drug treatment for combined conditions.