Community-acquired pneumonia is an inflammation of the lung parenchyma that occurs outside of the hospital or during the incubation period of a hospitalized patient. It is mostly caused by bacteria and usually requires regular treatment in the hospital. The timing of stopping medication is also different depending on the causative organism. For example, if there is no underlying disease in common community-acquired pneumonia and the fever subsides, the medication can be stopped in 3-5 days, and the course of treatment is about 7-10 days. Patients with Streptococcus pneumoniae infection can consider stopping the drug 72 hours after the fever subsides. Patients with underlying disease conditions, such as the elderly or long-term bed-ridden patients, patients with poor nutritional status, the withdrawal time should be longer, otherwise it will cause the infection to worsen. In the case of more extensive lesions, possibly severe pneumonia, hospitalization is necessary. At this time to stop the drug is not based on the fever disappeared a few days or how much time to decide, according to the clinical manifestations and pathogenetic examination to determine, may be in the middle of the repeated pathogenetic testing, it is easy to appear in the process of mixed infections, such as fungal infections in the process of medication, the condition will be repeated or even other conditions, the nutritional status will also affect the role of antibiotics, the infection is poorly controlled or more and more serious consequences, antibiotics are not entirely dependent on the disease, but also on the nutritional status of patients with poor control or more and more serious. Consequences, antibiotics are not entirely pathogenetic or time dependent. Atypical pathogen infections, such as chlamydia or mycoplasma, require a longer course of treatment of about 10-21 days. Different pathogens and different underlying conditions dictate different withdrawal times.