The time for food allergy to subside varies from person to person and is mainly related to the patient’s physical condition and the severity of the allergy. Food allergy is an allergic reaction that occurs after eating certain foods, such as nausea, vomiting, generalized rash and itching, and in severe cases, respiratory and circulatory failure and shock. The onset of food allergy varies, and the severity of the disease varies. Common allergic foods include milk, eggs, peanuts, nuts, seafood, soybeans and certain fruits. If the food allergy is mild, the patient can take vitamin C or anti-allergy medication and usually return to normal in a few hours. If the patient’s allergic reaction is more severe, timely anti-allergic treatment is recommended under the guidance of a doctor, and recovery can usually be achieved in 2-3 days. Patients with a history of food allergy should avoid foods with high allergenicity such as seafood and mangoes in daily life, eat more vitamin-rich fruits and vegetables, and exercise more to improve the body’s resistance.