Nasal congestion is among the most bothersome of the symptoms of intermittent allergic rhinitis (IAR). Decongestants such as pseudoephedrine are often accompanied by adverse effects and should be avoided by patients with hypertension, arrhythmia, and other medical conditions. Most of the currently available antihistamines are ineffective for nasal congestion. Oral desloratadine, a new, potent H1-receptor antagonist, was examined for its ability to relieve nasal congestion/stuffiness in 346 patients (172 in the desloratadine group and 174 in the placebo group) with IAR. Desloratadine, administered once daily at a dose of 5 mg, demonstrated significant improvement in nasal congestion/stuffiness at all time points assessed in the study. This benefit was observed as early as the first patient evaluation on day 2 and continued throughout the 2 weeks of the study. Desloratadine is a new treatment option for patients with IAR and nasal congestion.