Allergic rhintis patients givin fexofenadine capsules in closes of 60-240 mg.twice daily for 2 weeks or in 40 health volunteers given fexofenadine as an oral solution at doses up to 400 mg. Twice daily for 6 days. Pediatric patients from 2 placebo controlled trials treated with up to 60 mg fexofenadine twice daily demonstrated no significant treatment or dose-related increases in QTc.