Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect rates observed in practice. 

Azelastine hydrochloride nasal spray, 0.15%   
The safety data described below reflect exposure to azelastine hydrochloride nasal spray, 0.15% in 2114 patients (6 months of age and older) with seasonal or perennial allergic rhinitis from 10 clinical trials of 2 weeks to 12 months duration. In 8 double-blind, placebo-controlled clinical trials of 2 to 4 weeks duration, 1703 patients (646 males and 1059 females) with seasonal or perennial allergic rhinitis were treated with azelastine hydrochloride nasal spray, 0.15% one or two sprays per nostril once or twice daily. In the 12 month open-label, active-controlled clinical trial, 466 patients (156 males and 310 females) with perennial allergic rhinitis were treated with azelastine hydrochloride nasal spray, 0.15% two sprays per nostril twice daily. Of these 466 patients, 152 had participated in the 4-week placebo-controlled perennial allergic rhinitis clinical trials. In a 4-week, double-blind, placebo-controlled clinical trial, 161 patients (87 males and 74 females) ages 6 to 11 years of age with perennial allergic rhinitis, with or without concomitant seasonal allergic rhinitis, were treated with azelastine hydrochloride nasal spray, 0.15% one spray per nostril twice daily. In a 4-week clinical trial, 95 patients (59 males and 36 females) ages 6 months to 5 years of age with seasonal and/ or perennial allergic rhinitis were treated with azelastine hydrochloride nasal spray, 0.15% one spray per nostril twice daily. The racial distribution for the 10 clinical trials was 79% white, 14% black, 2% Asian, and 5% other. 

Adults and Adolescents 12 Years of Age and Older   
In the 7 placebo controlled clinical trials of 2 to 4 week duration, 2343 patients with seasonal allergic rhinitis and 540 patients with perennial allergic rhinitis were treated with two sprays per nostril of either azelastine hydrochloride nasal spray, 0.15% or placebo once or twice daily. Overall, adverse reactions were more common in the azelastine hydrochloride nasal spray, 0.15% treatment groups (16 to 31%) than in the placebo groups (11 to 24%). Overall, less than 2% of patients discontinued due to adverse reactions and withdrawal due to adverse reactions was similar among the treatment groups. 

Table 3 contains adverse reactions reported with frequencies greater than or equal to 2% and more frequently than placebo in patients treated with azelastine hydrochloride nasal spray, 0.15% in the seasonal and perennial allergic rhinitis controlled clinical trials.

In the above trials, somnolence was reported in <1% of patients treated with azelastine hydrochloride nasal spray, 0.15% (11 of 1544) or vehicle placebo (1 of 1339).

Long-Term (12 Month) Safety Trial   
In the 12 month, open-label, active-controlled, long-term safety trial, 466 patients (12 years of age and older) with perennial allergic rhinitis were treated with azelastine hydrochloride nasal spray, 0.15% two sprays per nostril twice daily and 237 patients were treated with mometasone nasal spray two sprays per nostril once daily. The most frequently reported adverse reactions (>5%) with azelastine hydrochloride nasal spray, 0.15% were bitter taste, headache, sinusitis, and epistaxis. Focused nasal examinations were performed and no nasal ulcerations or septal perforations were observed. In each treatment group, approximately 3% of patients had mild epistaxis. No patients had reports of severe epistaxis. Fifty-four patients (12%) treated with azelastine hydrochloride nasal spray, 0.15% and 17 patients (7%) treated with mometasone nasal spray discontinued from the trial due to adverse events.