Adverse reactions to Loratadine are dose related, transient, mild in severity, and occur infrequently. The central nervous system effects occurred most frequently, such as headache, sedation, drowsiness and fatigue. Dry mouth was also one of the most frequent effects. Wheezing, epistaxis and pharyngitis could be found in children. Other symptoms such as diarrhea, abdominal pain, conjunctivitis, earache, rash, influenza-like symptoms and viral infections, also occurred. Hypertension, hypotension, palpitation, tachycardia, arrhythmia, syncope, prolonged QT interval, abnormal hepatic function, including jaundice, hepatitis, hepatic necrosis were rarely occurred. Insomnia and nervousness also occurred in some patients.