The vaccination has a hard bump for half a month. If the local hard bump does not have symptoms such as redness, swelling, pain and itching, as well as general discomfort such as dizziness, weakness, fever and loss of appetite, no special treatment is generally required and can be relieved by local hot compresses. If the above-mentioned symptoms are accompanied by timely medical consultation, they are often related to drug malabsorption, improper living habits and infection at the vaccination site. 1. Drug malabsorption: Due to the special composition of some vaccines, or the slow absorption of vaccines caused by the patient’s own physical factors, the local appearance of hard bumps for a longer period of time is a normal phenomenon, which is considered to be a normal reaction caused by drug malabsorption. It can be relieved by applying topical magnesium sulfate, etc. If the patient is vaccinated with BCG, permanent scar will be formed; 2. Improper living habits: due to strenuous exercise, smoking, drinking alcohol after vaccination, or consumption of irritating foods such as chili, seafood, coffee, strong tea, etc., may cause redness and swelling of the vaccination site and the appearance of hard bumps. If the diet is not appropriate for a long time, it will affect the recovery of the hard bumps, resulting in a phenomenon that cannot subside for half a month. It is recommended that patients eat lightly, take sufficient rest and observe whether there is improvement; 3. Infection at the vaccination site: it is often related to water, pressure and rubbing at the vaccination site. In case of serious cases such as hematoma and abscess, surgical removal may be required.