Seasonal allergic rhinitis: limited effectiveness of treatments

(1) Seasonal allergic rhinitis, otherwise known as hayfever, is a harmless condition, although it can cause major discomfort and interfere with activities of daily living. We conducted a review of the literature, based on our in-house methodology, to determine the risk-benefits of treatments used in this setting. (2) Placebo-controlled trials show that sodium cromoglicate relieves symptoms, especially if it is used before symptoms appear. Adverse effects are rare with sodium cromoglicate nasal solutions and eye drops. (3) Nasal steroids have well-documented efficacy. Beclometasone is the best choice. Adverse effects include epistaxis, nasal irritation and, occasionally, systemic disorders. (4) Oral antihistamines are less effective than nasal steroids. They also provoke adverse effects, especially drowsiness. Nasal azelastine seems to have a similar efficacy as oral antihistamines. (5) The adverse effects of systemic steroids must not be overlooked, especially with long-term use. Oral administration is an alternative for severe symptoms that do not respond to other treatments, although this is rarely the case. Long-acting intramuscular steroids carry an increased risk of adverse effects. (6) Despite evaluation in several randomised controlled trials, there is no firm evidence that homeopathic preparations have any specific efficacy in allergic rhinitis. (7) Vasoconstrictors, ipratropium and montelukast, have negative risk-benefit balances in hay fever. (8) When a single allergen is responsible (grasses, ragweed, birch), clinical trials suggest that specific desensitisation can provide a modest improvement. However, this treatment carries a risk of local adverse effects, as well as a risk of rare but severe anaphylactic reactions, especially in patients who also have unstable severe asthma. (9) Sublingual desensitisation seems to be even less effective than subcutaneous desensitisation in adults. Follow-up is too short to know whether there is a risk of severe anaphylactic reactions. The results of paediatric studies are even less convincing. (10) In practice, when drug therapy is needed to relieve symptoms of seasonal allergic rhinitis, sodium cromoglicate is the first-line treatment. If a nasal steroid solution is chosen, it should be used for the shortest possible period.