A 3-month evaluation of electrocardiographic effects of loratadine in healthy individuals

This randomized, placebo-controlled, double-blind, outpatient study evaluat ed the effects of prolonged exposure to foul times the recommended daily do se of loratadine on electrocardiographic (ECG) parameters, including the QT (c) interval. Seventy adult men received either loratadine 40 mg once daily or placebo for 13 weeks. The primary safety variable was ECG parameters re corded at weeks 3, 5, 7, and 9, and 1 month after the final dose. No statis tically significant mean change from baseline in any ECC parameter or indiv idual trends suggesting QT(c) prolongation were observed. No patient had a QT(c) interval greater than 440 msec at any time point. Loratadine was well tolerated, and there were no reports of dizziness or syncope. Long-term ad ministration of loratadine 40 mg once daily was well tolerated and produced no evidence of QT(c) interval prolongation or any other cardiac arrhythmia s.