A recently synthesized, non-halogenated steroid, budesonide, with high local anti-inflammatory properties, but with low systemic effect, was tested as a nasal spray in the treatment of patients with perennial rhinitis. Used in a dose of 200 micrograms and 400 micrograms budesonide per day in a double-blind cross-over study in 36 patients it was found to have an excellent and dose-dependent effect on nasal blockage and discharge as well as on sneezing bouts. Budesonide caused a considerable decrease in the nasal symptoms in 21 patients with demonstrable cutaneous and RAST allergy, as well as in a group of 15 patients without. The same alleviation of symptoms was noted in 22 patients with nasal eosinophilia but not in a group of 14 patients without. To determine possible adverse reactions during long term treatment, 15 patients with perennial rhinitis used budesonide as a nasal spray for more than two years. No adverse reactions serious enough to discontinue the treatment were noted in any of the patients. Haematologic parameters as well as adrenal gland function were monitored throughout the first 1.5 years. No depression was noted. Biopsy specimens of the nasal mucosae did not show any significant evidence of increased metaplasia.