What Is the Connection between Leukotrienes and Asthma?

The relationship between leukotrienes and asthma is one of cause and effect. Antigens, foreign substances like dust and pollen, usually bring on asthma attacks. It is leukotrienes, however, that trigger the biological response that sets in motion an asthma attack. The action of leukotrienes in the asthmatic’s immune system is responsible for the body’s extreme reaction to antigens.

The body’s immune system contains signal molecules called eicosanoids. They act as a kind of early warning system to the portion of the body that produces them that it is in danger from some outside element. Leukotrienes are a type of signal molecule protecting the area of the lungs, and they send an alarm to the lung tissue at any threat that foreign substances are entering the body’s airways. The connection between leukotrienes and asthma is a direct one, in that leukotrienes set in motion the body’s defenses that ultimately cause an asthma attack.

The immune system of the asthmatic is hypersensitive to antigens. When confronted with these substances, which may be otherwise harmless to a non-asthmatic, the immune system begins to immediately close off access to the pathways to the lungs. It does this by constricting the veins and the arteries in the lung tissue. This arterial constriction is what causes chest pain and difficulty in breathing that is central to an asthma attack. As the size of veins and arteries decreases, pressure in the heart and lungs increases, and this results in the feeling of suffocation that asthma sufferers experience.

This signaling relationship between leukotrienes and asthma can be modified. There is a class of synthetic leukotriene modifiers, also called leukotriene inhibitors or leukotriene receptor antagonists. These modifiers are in pill form and block the triggering action of leukotriene molecules. The blocking action helps stop the immune system’s defenses from engaging. The modifiers change the reaction between the signaling cells and the lungs over time and must be taken continuously.

Leukotriene modifiers may sometimes prevent the symptoms of asthma from even occurring. They can also prevent or curtail the scarring and inflammation that can occur in the lung’s airways. These modifiers may not work for all asthma sufferers or may need to be taken in conjunction with other medications.

There are other methods of curtailing the effects of the causal relationship between leukotrienes and asthma attacks. Corticosteroids, for instance, are considered more powerful than leukotriene modifiers. Inhaled medications are a common form of long-term asthma treatment. Corticosteroids can be used to prevent and asthma attack and to reduce the effects of an attack when one occurs. Some asthmatics may need both inhaled medications and leukotriene inhibitors.