Asthma experts agree, however, that the first line of defense is avoidance of whatever brings on an acute asthma episode. Influenza or even cold viruses can also trigger asthma episodes. In other cases, the triggers cannot be identified, even after a thorough investigation. Asthma Drugs Knowing what provokes an asthma attack is critically important in prevention, but it's often difficult or impractical to avoid contact with triggering irritants. Today, however, physicians can prescribe drugs to lessen the risk of acute attacks after exposure to an offending irritant, as well as halt attacks that can't be prevented.
Some drugs do both.
A new class of oral anti-inflammatory controller drugs acts by blocking a certain part of the inflammation pathway. They don't provide immediate relief of symptoms, but their preventive action persists for many hours, which makes them useful in controlling attacks that might occur during hours of sleep. Drugs to bring quick relief in acute asthma attacks are chiefly short-acting inhaled bronchodilators that act rapidly but for a relatively brief time to relax bronchial constriction. Although these drugs are effective in treating asthma, there is some controversy about their safety, especially when they are overused. Scientific debate makes it clear, however, that an increasing need for inhaled bronchodilators, or a decreasing response to each dose, is a signal that the patient's asthma is not being adequately controlled.