Objective: To determine whether hypertonic saline nasal spray relieves nasal symptoms and shortens illness duration in patients with the common cold or acute rhinosinusitis. Design: Randomized trial with 2 control groups. Setting: Two family practice clinics. Participants: One hundred forty-three adult patients with a cold or sinus infection. Patients with allergic rhinitis, symptoms for more than 3 weeks, or other respiratory diagnoses were excluded, as were those who had used topical decongestants. Intervention: Hypertonic saline or normal saline spray 3 times a day or observation. Subjects completed a 7-day symptom checklist that included a well-being question ("Do you feel back to normal?"). Main Outcome Measures: Nasal symptom score (sum of scores for nasal congestion, rhinorrhea, and headache) on day 3 and day of well-being (day of symptom resolution). Results: Data were collected for 119 subjects. No difference was found in either primary outcome when hypertonic saline was compared with either normal saline or observation. Mean day of well-being was 8.3 (95% confidence interval [CI], 6.9-9.7), 9.2 (95% CI, 6.9-11.43), and 8.0 (95% CI, 6.7-9.3) days in the hypertonic saline, normal saline, and observation groups, respectively. Day 3 mean nasal symptom score was 3.8 (95% CI, 3.0-4.5) for hypertonic saline, 3.7 (95% CI, 2.9-4.5) for normal saline, and 4.1 (95% CI, 3.5-4.7) for observation. Only 44% of the patients would use the hypertonic saline spray again. Thirty-two percent noted burning, compared with 13% of the normal saline group (P=.05). Conclusion: Hypertonic saline does not improve nasal symptoms or illness duration in patients with the common cold or rhinosinusitis.