 Eligible participants completed the Rhinitis Quality of Life Questionnaire RQLQ and underwent measurement of nasal volume by acoustic rhinometry before starting the study. Participants were instructed to keep a diary of daily symptoms, nasal peak inspiratory flow NPIF meter readings, and medication use during the study; no rescue medications were allowed. The severity of sneezing, rhinorrhea, nasal congestion, and other symptoms was recorded in the morning reflective of symptoms overnight and evening reflective of daytime symptoms on a 0 to 3 scale. Intake of the study medication was performed once daily, at night, after recording of symptoms and NPIF values. Subjects returned to the nasal laboratory every 2 weeks for a total of 4 weeks for review of the symptom diaries, replacement of medications, performance of acoustic rhinometry, and completion of the RQLQ. After the fourth week, participants stopped treatment, returned medication, and continued with the clinical trial for 2 additional weeks. During this time, they maintained symptom diaries and NPIF measurements twice daily. At the end of the 2-week period, participants returned to the nasal laboratory to perform a final acoustic rhinometry, complete an RQLQ survey, and return the diaries. 