Ketotifen is an antiallergic and asthma medication that acts primarily as an antiallergic and mildly anti-inflammatory agent for the prevention of bronchial asthma. Ketotifen is an H1 receptor blocking drug, which can inhibit the release of allergic reaction mediators, inhibit airway spasm caused by antigens and non-specific stimuli, and also has a powerful H1 receptor blocking effect, enhancing the asthma-alleviating effect of β2 agonists. Clinically, it can be used in combination with aminophylline and salbutamol to enhance the effect of action, treatment and prevention of asthma. Ketotifen commonly used preparation for ketotifen fumarate tablets, can be used to treat allergic rhinitis, allergic bronchial asthma and other diseases, adverse reactions include drowsiness, dry mouth, nausea, headache, dizziness, etc., the drug needs to be used under the guidance of a professional doctor, it is recommended to consult a doctor, standardized treatment.