Levocetirizine as a kind of antihistamine, there is no clear regulation levocetirizine anti-skin allergy can be taken for a few days at most, generally need to be based on the severity of the disease and the patient’s post-drug reaction and so on comprehensive judgment. Levocetirizine belongs to the third generation of antihistamines, used in the treatment of skin allergies with tablets and oral liquid two preparations, its main ingredient is levocetirizine hydrochloride, applicable to allergy-induced urticaria, dermatitis eczema, itchy skin and allergic rhinitis, allergic conjunctivitis and other diseases. The drug works fast and is safe, with fewer adverse reactions, common adverse reactions include drowsiness, fatigue, etc. However, there is no evidence that levocetirizine can be used for a maximum of a few days, and it is generally necessary to follow the doctor’s instructions for use of the drug, which is contraindicated in allergy to piperazine derivatives, patients with specific hereditary diseases, and patients with end-stage renal disease. Levocetirizine is only symptomatic treatment, such as the occurrence of symptoms related to skin allergies, it is recommended to go to the hospital in a timely manner, to clarify the cause of the disease, under the guidance of the doctor reasonable use of medication, avoid self-administration.