Introduction: Hay fever is found throughout the world. Epidemiological evidence suggests considerable geographical variation in its prevalence. Symptoms are caused by an IgE-mediated type 1 hypersensitivity reaction to airborne allergens such as pollen or fungal spores, and may also cause eye, sinus, respiratory, and systemic problems.
Methods and outcomes: We conducted a systematic review and aimed to answer the following clinical question: What are the effects of treatments for hay fever in adolescents and adults? We searched: Medline, Embase, The Cochrane Library, and other important databases up to April 2008 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
Results: We found 211 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
Conclusions: In this systematic review we present information relating to the effectiveness and safety of the following interventions: intranasal corticosteroids, oral antihistamines, intranasal antihistamines, oral leukotriene receptor antagonists, systemic corticosteroids, intranasal ipratropium bromide, oral decongestants, and combinations of these treatments.