Comparison of loratadine and terfenadine in allergic seasonal rhinoconjunctivitis with emphasis on nasal stuffiness and peak flow.

ABSTRACT

Non-sedating antihistamines have been used in the treatment of allergic rhinoconjunctivitis. Recommended dosage of loratadine (CAS 79794-75-5) is 10 mg once daily, whereas terfenadine (CAS 50679-08-8) until recently has been recommended as 60 mg twice daily. 105 patients took part in this double-blind 3-week controlled study comparing loratadine 10 mg once daily to terfenadine 120 mg once daily. Patient's daily symptom score and physician's assessment of symptoms, treatment effect and anterior rhinoscopy were evaluated as well as an objective parameter, nasal peak flow. In addition nasal peak flow was compared to patient's symptom score of stuffiness. A significant treatment effect in both treatment groups was found but there was no statistically significant difference between the two groups. Correlation between patient's feeling of stuffiness and nasal peak flow was significant. It is concluded that loratadine 10 mg once daily is as effective as terfenadine 120 mg once daily in controlling allergic rhinoconjunctivitis, and that patients' feeling of stuffiness correlates well to nasal peak flow.