Loratadine is a commonly used anti-allergy, antihistamine drug that can be used to treat allergic conjunctivitis, allergic rhinitis, including seasonal allergic rhinitis and perennial allergic rhinitis, as well as localized skin allergies, such as urticaria and pruritus. The general dosage of loratadine for adults is 10 mg once a day. Although it is a non-sedating antihistamine, which means that it causes drowsiness and lethargy very slightly, individual sensitive people still have drowsiness and drowsiness after taking the drug, so it is recommended that loratadine should be taken at night to reduce drowsiness and lethargy after taking the drug during the day. The antihistamine effect of loratadine is generally 10mg per day at night, that is, one tablet, taking too large a dose, there is no significant increase in efficacy, but may increase the side effects, adults generally take 10mg at a time, once a day at night.