Air passages will react more quickly to triggers if inflammation is already present in the airways. Smoke acts as a very strong trigger. Second-hand smoke has been shown to aggravate asthma symptoms, especially in children. The effects of one cigarette lingers for 7 days. Asthma attacks can be mild, moderate, or severe, and can last for a few minutes, a few hours, or several days.
Attacks can occur anywhere and at any time.
Many attacks occur at night. Sometimes, there are warning signs that an attack is about to happen, but sometimes there aren't. Asthma has been identified as an atopic disease. This is the result of certain inherited genetic features that cause the immune system to respond to otherwise innocuous proteins as if they were dangerous invaders. An asthma episode feels similar to taking deep breaths of very cold air on a winter day.