Hypoglycemic symptoms such as dizziness, nausea, and weakness of the limbs may easily occur after vaccination on an empty stomach. These symptoms are easily confused with adverse reactions to vaccines, and treatment may be delayed if the uncomfortable symptoms of vaccination cannot be detected in time after they occur. For some vaccinators who have hypoglycemia themselves, vaccination on an empty stomach may easily trigger a series of uncomfortable symptoms such as sweating, palpitations, hunger, tremor, dizziness, and even dizziness. This is especially true for some popular vaccinations, which may require long queues, making it easier for the vaccinees to lose weight or even pass out. Vaccination on an empty stomach may also lead to aggravation of adverse reactions to vaccines. The human body is mostly in a state of stress when fasting, due to low blood sugar levels and poor central regulation, etc. If the vaccinator is weak, it is easy to cause disorders in the immune system and relatively poor immune regulation of vaccines, leading to the appearance and aggravation of various adverse reactions to vaccines. In particular, for vaccination of children, an empty stomach may cause crying and refusal to cooperate. However, it is important to note that not all vaccines are prohibited on an empty stomach. For example, for rotavirus vaccine, polio vaccine and some oral vaccines for young children, it is recommended to avoid breastfeeding and drinking hot water half an hour before and after vaccination to prevent spitting out the oral vaccine pills after vaccination due to vomiting of milk and water, which may reduce the effect of the vaccine. In addition, before and after vaccination, the vaccinated person can take a light and easily digestible diet in moderation, with less oil and salt, less spices and less sugar in cooking. After the vaccination, the body is weak, so the diet should be less of seafood, mutton, eggs, milk and other idiopathic foods, but also pay attention to the meat and vegetarian mix to prevent partial diet.