Ketotifen children’s dosage is generally less than the adult dosage, children are one-third or two-thirds of the adult dosage, the specific should be based on the doctor’s recommendations. Ketotifen tablets are suitable for allergic rhinitis and allergic bronchial asthma, adult dosage is usually 1 tablet/times, 2 times/day, children under 12 years of age should reduce the dosage on this basis, usually one-third or two-thirds of the adult dosage, but the specific dosage is recommended to consult a doctor according to the condition. If adverse reactions such as dry mouth, drowsiness, nausea, fatigue, dizziness and headache occur after taking the drug, or allergic reactions, it is recommended to stop using the drug and go to the hospital in time for examination and treatment under the guidance of a physician.