Allergic cough in three or four year old children should look for allergens and avoid contact, along with cough suppressants, hormonal drugs and antihistamines. 1. Cough suppressants: Pentoxyverine Pentoxyverine is a non-addictive cough suppressant, used for various causes of dry cough, can have a respiratory inhibition of the central nervous system, reduce cough reflex. Occasionally constipation, mild dizziness, headache, nausea, diarrhea and other adverse reactions, glaucoma and cardiac insufficiency should be used with caution. children under the age of 5 years should be taken under medical supervision. 2. Hormonal drugs: commonly used hormonal drugs are prednisone, dexamethasone and so on. Inhaled glucocorticosteroids can be used if the symptoms are severe. Children’s medication should be used under the explicit use of a doctor. Allergic to the product is prohibited. 3. Antihistamines: commonly used drugs are loratadine syrup and so on. This product is prohibited for those who are allergic to it. In addition to clear allergens, can be desensitized treatment. Children with allergic cough should pay attention to avoid contact with allergens, exercise to increase resistance, and apply medication under the guidance of a doctor.