This multicentre double-blind, placebo controlled study had a practical objective, based on the expectation that many patients with
seasonal allergic rhinitis will be prescribed oral
antihistamine monotherapy by their primary care physician, whereas
allergy specialists are more likely to prescribe combination
therapy including
antiinflammatories. The specific question was, "Will the addition of
nedocromil sodium 1%
nasal spray to
astemizole tablets improve control of symptoms of
seasonal allergic rhinitis induced by
ragweed pollen, as compared to
astemizole therapy alone?'. Following a one-week baseline, planned to coincide with the start of the local
ragweed pollen season, patients (aged 12-64) were randomly assigned to four weeks' double-blind test treatment with either
nedocromil sodium 1%
nasal spray four times daily (QID) +
astemizole (n = 146) or placebo
nasal spray +
astemizole (n = 148) or double-dummy (
nasal spray + capsules) placebo (n = 71). Patient diary cards were kept throughout the five weeks, and
clinic visits were made before and after baseline and after one and four weeks' treatment. During the 10-day peak pollen period, the diary card
rhinitis symptom summary score (0-4 severity scale) was significantly reduced in patients receiving either
astemizole alone (p < 0.001) or the combination
therapy (p < 0.001) as compared with placebo. Direct comparison of the active treatments further showed that symptoms were significantly less severe (p < 0.01) with the combined
therapy than with
astemizole alone, and this despite significantly greater reliance on permitted rescue medications (p < 0.05 for
pseudoephedrine usage) in the
astemizole group. Clinical assessments of
rhinitis made during the peak pollen visit, after the first week of test treatment, were also significantly (p < 0.05 - p < 0.01) in favour of combined
therapy with
nedocromil sodium 1%
nasal spray +
astemizole rather than
astemizole alone, and at the same time this preference was confirmed by physician (p = 0.011) and patient (p = 0.003) opinions of symptom control. In conclusion, this antiinflammatory +
antihistamine treatment proved superior to
antihistamine alone for effective management of
allergic rhinitis. The combined
therapy worked quickly and was well-tolerated, with no serious adverse events or untoward effects on blood or urine variables.