If you have asthma, you are more likely to experience this condition due to so many reasons. Asthma gets worse in the night because your chances of getting exposed to its triggers are very high in the night. Asthma triggers are allergens, emotional stress, smoke, cold hair, etc. There are different kinds of microorganisms that are basically asthma triggers; they live tightly around your bed. That's why when you sleep in the night, and they gain entry into your airways, they might cause the inflammation of the airways, and this will also cause the airways to become narrow.
Having pets around in your room can also flare up this condition in the night. Most of these pets release their dander, and when they spend so much time in your room, these particles will be everywhere in your room, especially on your bed. Animal dander can also trigger asthma. The air tends to become cold during the night, that's why your asthma could get worse in the night, especially when you get exposed to too much of it.
The exact reason why asthma is worse at night is not clear, but there is a popular explanation of why this happens. When you sleep at night, your body goes through hormonal changes, which can cause asthma to be worse. Your body releases higher levels of a hormone called cortisol (also known as the stress hormone). This hormone can cause inflammation (swelling) of the airways, which can trigger coughing, trouble breathing, and chest pain. Another explanation is that when you sleep, you might be exposed to allergens such as dust mites and animal dander, and being in a reclining position can causes changes in bronchial function. To prevent asthma attacks at night: avoid pets in your bedroom, wash and change your bed linen often, avoid sleeping close to strong odor such as perfumes, and use covers to prevent dust mites.
Asthma is one of the conditions in which your airways become narrow, swell and it will also produce exceeded mucus. During the night, it becomes worse why because, at night, our body will release higher levels of the stress hormone, which may produce inflammations in your airways.