Budesonide, a topical corticosteroid used in the treatment of seasonal allergic rhinitis, can be administered to the nose as an aerosol via a pressurized metered dose inhaler (pMDI) or as a metered nasal pump spray. Studies have shown that about 64% (256 μg) of a nominal dose of 400 μg budesonide pMDI preparation is delivered to the patient compared with 100% of the nominal dose of the pump spray. The present study was undertaken to assess the efficacy and safety of budesonide delivered via a nasal pMDI twice daily (Rhinocort®pMDI, at 400 μg/day) with an aqueous suspension of budesonide delivered via a metered nasal pump spray once daily (Rhinocort®Aqua, at 256 μg/day or 400 μg/day). The multicenter, double-blind, randomized, placebo-controlled, parallel-group study was conducted in 318 patients (154 men, 164 women; aged 12–67 years) with ragweed-induced seasonal allergic rhinitis. A 1-week baseline period was followed by a 3-week treatment. Nasal symptoms were recorded by the patients, adverse events were noted, an overall evaluation of treatment efficacy was made, and urine cortisol and creatinine levels were measured. Substantial or total control of symptoms was achieved in 83.8% of patients treated with 256 μg of aqueous budesonide, 76.3% with 400 μg of aqueous budesonide, and 80.8% with 400 μg of budesonide pMDI; these were all significantly different (p < 0.001) compared with placebo (23.4% of patients). There were no significant differences in the 24-hour urine cortisol levels between the groups and there were few, infrequent adverse events, similar between the groups and resolved completely on discontinuation of treatment. It was concluded that budesonide, given once daily as 256 μg or 400 μg in an aqueous suspension or twice daily as 400 μg in a pMDI provides good alleviation of the symptoms of seasonal allergic rhinitis with no significant risk of suppression of urine cortisol.