Abstract
The mainstay of chronic asthma management consists of using pharmacological agents that induce broncho-dilatation, such as short-acting β-adrenergic receptor agonists (bronchodilators or relievers), and that control the chronic inflammatory process, such as cortico-steroids (anti-inflammatory or controllers). Short-acting β-adrenergic receptor agonists are the best relievers, whereas inhaled corticosteroids, by inhibiting eosino-philic and lymphocytic inflammation and mediator/cytokine expression, remain the mainstay chronic treatment of asthma. Long-acting β-adrenergic receptor agonists are best used in conjunction with inhaled corticosteroids, providing additive bronchodilatation, better asthma control and reduced exacerbation rates in patients with moderate to severe asthma. Slow-release theophylline combines bronchodilator and some anti-inflammatory effects and is best used in combination with inhaled corticosteroids. Leukotriene inhibitors, by either inhibiting the effects of cysteinyl leukotrienes or reducing their production, also cause some bronchodilator effects with inhibition of eosino-philic inflammation. They are effective in mild-to-moderate asthma, but low-dose inhaled steroids are more efficacious; leukotriene inhibitors also provide additive effects in combination with inhaled steroids. Increased understanding of the immunology and inflammatory responses has led to the identification of novel targets and to the development of potentially new therapies. These include immunologic targets, such as those against T cells and T cell-related targets, anti-cytokine therapies and anti-IgE approaches. New effective therapies are particularly needed for patients with severe asthma who do not respond to currently avail-able treatments.
