The onset of asthma is closely related to the change of climate, and many asthma patients may know this very well. Every late spring (April and May) and early autumn (September and October), asthma will be aggravated, but really in the hot summer and cold winter but alleviated, unlike the common “old slow branch”. The reason for this is, first of all, the influence of temperature, humidity and air pressure. Sudden changes in temperature may affect the body’s neurological, endocrine and immune functions, easily causing the onset of disease. High humidity can increase the body’s respiratory rate, thus triggering asthma. At the same time, high humidity can promote the reproduction of bacteria and dust mites; on the contrary, low humidity can make the respiratory mucosa dry and the airway epithelium damaged, thus aggravating the disease. Low air pressure can make various allergens such as pollen, dust mites, animal fur, bacteria, dust and industrial irritants easily scattered to low places and inhaled into the respiratory tract, stimulating asthma. Some thunderstorms can also increase the incidence of asthma. Secondly, late spring and early fall is the season when many plants are in bloom and plant allergens, such as pollen, are one of the main causes of asthma onset. There are many types, densities and quantities of inhalant allergens floating in the air during spring and autumn. The main cause of seasonal asthma attacks is high exposure to these allergens. The pollen season of sycamore, mulberry, willow and maple poplar in the coastal areas of southern China is in spring, thus increasing the number of asthma attacks between May and June in late spring and early summer. The pollen season of herbaceous pollen and artemisia plants, which are common in the north of China, is in late summer and early autumn, while seed pollen is more in late autumn, so the peak of asthma attacks is also from September to November every year. To prevent seasonal asthma attacks, the following points should be noted: 1. Clearly identify the allergens that trigger asthma and try to avoid them By recalling the medical history in detail, in many cases the factors that trigger asthma can be clearly identified. 70% to 80% of allergic asthmatics are allergic to dust mites. If the onset of asthma occurs during the rainy season, it often suggests a fungal allergy, and if the onset of asthma occurs in mid- to late-April, it is likely that the patient is allergic to sycamore pollen. To further identify allergens, patients can undergo skin tests or serum specific IgE tests at the hospital. The allergens that have been identified should be avoided or reduced as much as possible, and may even be moved to the ground for treatment. 2, avoid non-specific stimulation of the surrounding environment In the south, spring is generally the rainy season, and even often thunderstorms. This time the air humidity, in addition to fungal reproduction accelerated, low air pressure, thunderstorms when the atmosphere increased ozone. In addition, the dry climate in autumn and early winter as well as the strong cold wind stimulation that is common in the north of China are important non-specific stimulating factors for asthma attacks. Therefore, asthma patients should make it a habit to listen to the weather forecast and increase or decrease their clothing according to the weather changes. In case of such weather, it is better not to go out or to take preventive measures such as wearing a clean mask. If walking on the street is suddenly hit by strong wind, patients should walk with the wind at their back to avoid the stimulation of cold air against the wind. To prevent airway allergic inflammation due to seasonal inhalation of certain allergens, corticosteroids such as sodium cromoglycate and/or beclomethasone or budesonide or fluticasone can be inhaled before the attack season under the guidance of a specialist to suppress airway allergic inflammation and reduce airway reactivity. Specific use: Inhaled corticosteroids can be started about 2 weeks before the asthma attack season as prophylactic treatment, while oral or intravenous hormones should not be used as prophylactic medication for seasonal asthma. 4.Desensitization treatment before the prevalent season When seasonal allergens are identified, especially pollen and fungi, which are difficult to avoid contact with, patients should go to the hospital and start desensitization treatment 2 to 3 months before the asthma attack season under the guidance of a specialist, and if there is an effect, it should be adhered to for a long time and medication should be taken as prescribed during the attack season. In short, there are ways to prevent and control seasonal asthma attacks by doing the above.