Clarityn Allergy 1mg/ml Syrup Clarityn Allergy 1mg/ml Syrup contains the active ingredient loratadine, an antihistamine which helps to reduce your allergy symptoms by stopping the effects of a substance called "histamine", which is produced in the body when you are allergic to something. Clarityn Allergy 1mg/ml Syrup relieves the symptoms associated with allergic rhinitis (for example, hayfever), such as sneezing, runny or itchy nose & burning or itchy eyes & may also be used to help relieve symptoms of urticaria (itching & redness), which is often known as hives or nettle rash. Clarityn Allergy 1mg/ml Syrup is suitable for adults & children over the age of 2 years. The effects will last a whole day & should help you to continue your normal daily activities & to sleep at night.