Inhaled Drug Therapy-Associated Adverse Reactions in Obstructive Respiratory Diseases: A Review of a Decade of Reporting to the Portuguese Pharmacovigilance System

Inhaled medication used for treatment of chronic obstructive lung diseases (asthma, chronic obstructive pulmonary disease-COPD, and Asthma-COPD overlap) may be associated with adverse drug reactions (ADRs). The aim of this study was to characterise spontaneous reports (SRs) of suspected ADRs received by the Portuguese Pharmacovigilance System (PPS), from 2007 to 2017. Methods: Retrospective observational study of SRs associated with single substance and combination inhalers, analysed in terms of pharmacological class of the involved drugs, sex and age range of the involved patients, and seriousness and type of ADRs. Results: 230 SRs were analysed, accounting for a total of 599 suspected ADRs. Inhaled corticosteroid/long-acting beta-2 agonist combination had the highest frequency in SRs (32.2%) and in ADRs (32.7%). There was a slight predominance in men (51.3%) and non-elderly adults were the most affected age group (39.1%). Most SRs were serious (70.4%). In total, “respiratory, thoracic and mediastinal diseases” ADRs were the most reported (19.5%), with “dyspnea” being the most frequent (4.8%). Conclusions: Most SRs were associated with controller medications and were expected. Most ADRs involved non-elderly adults, were serious and of respiratory nature and many were due to overuse of reliever medication.