Theophylline is a purine class of drugs, with cardiotonic diuretic, relieve bronchospasm. Functions as bronchial asthma, chronic bronchitis, chronic obstructive pulmonary disease, acute bronchitis. Symptoms of wheezing in combination with beta agonists can improve the efficacy of bronchodilatation, but also with glucocorticoids. Also can be used for biliary colic, also can be used in the treatment of acute cardiac insufficiency and cardiogenic asthma, common adverse reactions are nausea, vomiting, headache, loss of appetite, panic, a small number of patients can be skin allergic reactions, the use of individual differences are relatively large, to do a good job of blood concentration monitoring.