What is the mechanism of action for salmeterol (Serevent) in asthma treatment?

Salmeterol is a long-acting beta-2 adrenergic agonist (LABA) that primarily works by relaxing bronchial smooth muscle. This action is achieved through the stimulation of beta-2 adrenergic receptors located on the smooth muscle cells of the airways. When these receptors are activated, a cascade of events occurs that leads to muscle relaxation and subsequent bronchodilation. This mechanism helps to alleviate asthma symptoms by opening the airways and making it easier for patients to breathe.

This bronchodilation effect is particularly beneficial during asthma exacerbations or in the management of chronic asthma, providing sustained relief for up to 12 hours or longer. It’s important to note that while salmeterol is effective in reducing symptoms, it does not have significant anti-inflammatory properties itself; hence, it is often used as an adjunctive therapy alongside corticosteroids, which address the underlying inflammation in asthma.