Brompheniramine, loratadine, and placebo in allergic rhinitis: a placebo-controlled comparative clinical trial

Abstract

A double-blind, randomized, placebo-controlled, parallel-group, multicenter study was conducted to compare the effectiveness of an extended-release formulation of a classical antihistamine, brompheniramine, and a second-generation compound, loratadine, in the treatment of allergic rhinitis. Subjects with symptoms of allergic rhinitis received brompheniramine 12 mg twice daily (n = 112), loratadine 10 mg once daily (n = 112), or placebo twice daily (n = 114) for 7 days. Study medications were blinded using a double-dummy technique. Subjects completed an overall evaluation of symptom relief on a daily basis and returned on treatment days 3 and 7, at which times the investigator assessed symptom severity. The investigator and subject each completed a global efficacy evaluation, and subjects were interviewed regarding adverse experiences. The primary efficacy variable was the physicians' global efficacy evaluation on day 3. Symptoms also were analyzed as summed severity scores for all symptoms and for the nasal symptom cluster of rhinorrhea, sneezing, and nasal blockage. At all post-baseline evaluations (days 3, 7, and averaged over the two days), brompheniramine was significantly better than loratadine and placebo for both sets of summed symptom scores and all three global assessments. Loratadine was significantly better than placebo for physician ratings of total symptom severity averaged over the two days and for the physician and subject ratings of the nasal cluster on day 3. Central nervous system-related symptoms were the most frequently reported adverse experiences; somnolence was reported most frequently by patients taking brompheniramine, and its occurrence was less frequent as treatment continued. A nonprescription, extended-release formulation of brompheniramine 12 mg twice daily provided significantly better relief of symptomatic allergic rhinitis than loratadine 10 mg once daily.