Allergy and poisoning are not the same. Poisoning refers to the physical and chemical damage caused by certain toxic substances to the human body, and all people may have a toxic reaction to toxic substances; allergy refers to the abnormal reaction of some special people (allergic body) caused by certain sensitizing substances (generally common substances in life, without toxicity). In short, poisoning is the abnormal reaction of ordinary people to special substances, while allergic reaction is the abnormal reaction of people with special constitution to ordinary substances. Another difference between allergy and poisoning is that the degree of poisoning is directly proportional to the amount of exposure to the harmful substance. The more harmful substances accumulate in the body, the more serious the poisoning; whereas allergy is not related to the amount of exposure to allergens, but only to the number of times of exposure. Generally speaking, the first time the human body comes into contact with a certain allergen is generally not morbid, but to make the body form a sensitized state. An allergic reaction occurs only when the same allergen is exposed again in the future.