If the cough is worse after taking cough medicine, it may be due to the fact that it has not worked for a relatively short period of time, or it may be caused by taking this medicine orally inappropriately. It is best to go to the hospital for a checkup and use medication under the guidance of the doctor. Generally, you need to go to the hospital to register with the respiratory medicine department, check the blood routine, C-reactive protein, take a chest X-ray or do a lung CT examination. If asthma is suspected, an airway reactivity test is also needed, mainly a tracheal provocation test and a bronchodilatation test. If the asthma is caused by cough variant asthma, treatment with only cough suppressant medication is not very effective and bronchodilators or hormonal medication is needed. If the cough is caused by inflammation, treatment with effective antibacterial drugs is also required.