Asthma

Understanding Asthma and its Treatment

• Asthma is a condition characterized by widespread, reversible narrowing of bronchial airways due to lymphocytic, eosinophilic inflammation of the bronchial mucosa.
• It can be classified based on its severity into mild intermittent, mild persistent, moderate persistent, and severe persistent.
• The clinical presentation of asthma includes shortness of breath, chest tightness, wheezing, and coughing.
• The pathogenesis of asthma is mediated by IgE in response to allergens such as dust mites, cockroaches, animal danders, molds, and pollens.
• The agents used in the treatment of asthma can be classified into short-term relievers and long-term controllers.
• Short-term relievers or bronchodilators include adrenoreceptor agonists or sympathomimetic agents, which relax airway smooth muscles and inhibit the release of bronchoconstricting mediators.
• Inhaled corticosteroids are used as long-term controllers or anti-inflammatory agents.
• Adrenaline and ephedrine are sympathomimetic agents that stimulate alpha-1, beta-1, and beta-2 receptors and are mostly used for the treatment of anaphylaxis.
• Salbutamol, salmeterol, formoterol, and terbutaline are beta-2 selective drugs that selectively bind to beta-2 receptors and are used for the relief of acute asthma attacks or maintenance therapy for patients with chronic asthma.
• Methylxanthine drugs such as theophylline, theobromine, and caffeine are derived from tea, cocoa, and coffee and have multiple proposed mechanisms of action, including inhibiting phosphodiesterase enzyme, inhibiting adenosine receptors, and deacetylating histones.
• Theophylline has been used in the treatment of asthma, but its use has declined due to the development of better alternatives.
• Nebulized therapy should be reserved for patients who are unable to coordinate inhalation from metered-dose inhalers, and methylxanthine drugs should be used with caution due to their potential side effects.