In winter, the cold air is so strong and cool that the flowers are gone, the grass is withered, and everything is latent and closed. The activity of some allergens also enters a low point, and patients who are allergic to them can be “relieved”. Winter is indeed the off-season for the onset of allergic diseases. However, allergic diseases do not stop coming in the winter. As the temperature drops, people’s indoor activities increase, opening windows and ventilation decrease, in addition to the use of heating, air conditioning, humidifiers, resulting in relatively high indoor temperature and humidity, and poor ventilation environment, coupled with the increased number of pets, resulting in a small environment created by people “crisis”, dust mites, mold, pet fur, etc. Dust mites, molds, pet fur, etc. may become pathogenic allergens for people with atopic conditions. Among the patients we see with allergic diseases, there are examples of those who develop only in winter. Therefore, we remind patients suffering from allergic diseases and those who are susceptible to them not to relax their vigilance, adhere to regular treatment and take good protection. First of all, avoid allergens and do not slacken off because of the cold weather. Common allergens are mainly dust mites, which like warm, humid environments and die in dry environments with humidity below 15% and cannot reproduce further in cold environments, but traditional insecticides cannot kill them completely. Frequent window ventilation and diligent bedding drying are cost-effective ways to prevent mites. In addition, regular cleaning of humidifiers, air conditioners, etc. to avoid mold breeding, regular bathing of pets and keeping them away from the bedroom to avoid the allergens they carry. Secondly, if symptoms appear, you should seek medical attention in time to avoid delaying the diagnosis and treatment. Patients who have symptoms in other seasons should not stop taking their own medication after winter because their symptoms have decreased, but should follow the doctor’s instructions to adjust the treatment plan to ensure the continuity of treatment. Once again, allergic diseases are systemic diseases, which can be manifested as the onset of an organ, or predominantly an organ, or “wandering”, with recurrent attacks, regularity, “self-healing” and other characteristics, and symptomatic treatment alone cannot fundamentally stop the natural progression of the disease. It is necessary to seek specialist consultation and receive timely and standardized diagnosis and treatment.