Hay fever and a single intramuscular injection of corticosteroid: a systematic review

Abstract

In severe hay fever, some patients are strongly affected despite the use of first-line therapy and are therefore treated with an intramuscular injection of systemic corticosteroid (i.m. SCS) in some countries. The aim of this paper was to explore the efficacy and side effects of a single i.m. SCS injection in hay fever in adults. PubMed, EMBASE, Cochrane Library. Systematic review. Criteria for inclusion: hay fever or seasonal allergic rhinitis, adults, injectable steroids, clinical trials, English language. None of the clinical trials were excluded, since an important aim of the review was to identify any possible side-effects. clinical effects, and clinical and physiological side-effects. 18 clinical trials met the inclusion criteria: nine double-blind RCTs (five placebo-controlled and four comparative RCTs), two single-blinded RCTs, and seven open trials. All studies were conducted before 1988. The efficacy of a single intramuscular injection of SCS was statistically significant in all five placebo-controlled trials and demonstrated considerable clinical benefit, lasting approximately from within the first day to four weeks. In the only two studies comparing i.m. SCS to nasal steroids a superior effect with i.m. SCS was demonstrated. The side-effects were few, both clinically and physiologically, with retained ability to respond to stress with hypothalamic-pituitary-adrenal activation. The studies in this review were sound and their findings consistent: i.m. SCS therapy was shown to be efficient and safe for the treatment of hayfever in adults. This review shows no support for any concerns regarding serious tissue atrophy or other serious side-effects, any long-lasting suppression of plasma-cortisol, or any influence on stress reaction, following a single intramuscular injection of SCS.