Short-acting β agonists |
Albuterol | Beta2-selective agonist • bronchodilation | Asthma acute attack relief drug of choice (not for prophylaxis) | Inhalation (aerosol) Duration: 2–4 h | Tremor, tachycardia |
Metaproterenol, terbutaline: similar to albuterol; terbutaline also available as oral and parenteral formulations |
Long-acting β agonists |
Salmeterol, formoterol, indacaterol, vilanterol | Beta2-selective agonists; bronchodilation; potentiation of corticosteroid action | Asthma prophylaxis (not for acute relief) • indacaterol and vilanterol for COPD | Inhalation (aerosol) Duration: 12–24 h | Tremor, tachycardia, cardiovascular events |
Nonselective sympathomimetics |
Epinephrine, isoproterenol | Nonselective β activation • epinephrine also an α agonist | Asthma (obsolete) | Inhalation (aerosol, nebulizer) Duration: 1–2 h | Excess sympathomimetic effect (Chapter 9) |
Indirect-acting sympathomimetic |
Ephedrine | Releases stored catecholamines • causes nonselective sympathetic effects | Asthma (obsolete) | Oral Duration: 6–8 h | Insomnia, tremor, anorexia, arrhythmias |
Methylxanthines |
Theophylline | Phosphodiesterase inhibition, adenosine receptor antagonist • other effects poorly understood | Asthma, especially prophylaxis against nocturnal attacks | Oral slow-release Duration: 12 h | Insomnia, tremor, anorexia, seizures, arrhythmias |
Roflumilast: a nonpurine molecule with effects similar to theophylline but more selective for PDE4; approved for COPD |
Caffeine: similar to theophylline with increased CNS effect, not used in asthma or COPD |
Theobromine: similar to theophylline with increased cardiac effect, not used in asthma or COPD |
Antimuscarinic agents |
Ipratropium, tiotropium, aclidinium | Competitive pharmacologic muscarinic antagonists | Asthma and chronic obstructive pulmonary disease | Inhalation (aerosol) Duration: several hours | Dry mouth, cough |
Unknown mechanism, possibly mast cell stabilizers |
Cromolyn, nedocromil | Reduce release of inflammatory and bronchoconstrictor mediators from sensitized mast cells | Rarely used prophylaxis of asthma; cromolyn also used for ophthalmic, nasopharyngeal, and gastrointestinal allergy | Inhaled aerosol for asthma • cromolyn local application for other applications Duration: 3–6 h | Cough |
Leukotriene antagonists |
Montelukast, zafirlukast | Pharmacologic antagonists at LTD4 receptors | Prophylaxis of asthma | Oral Duration: 12–24 h | Minimal |
Zileuton | Inhibitor of lipoxygenase • reduces synthesis of leukotrienes | Prophylaxis of asthma | Oral Duration: 12 h | Elevation of liver enzymes |
Corticosteroids |
Inhaled |
Beclomethasone, others | Inhibition of phospholipase A2 • reduces expression of cyclooxygenase | Prophylaxis of asthma: drugs of choice | Inhalation Duration: 10–12 h | Pharyngeal candidiasis • minimal systemic steroid toxicity (eg, adrenal suppression) |
Systemic |
Prednisone, others | Like inhaled corticosteroids | Treatment of severe refractory chronic asthma | Oral Duration: 12–24 h | See Chapter 39 |
Prednisolone: parenteral for status asthmaticus; similar to prednisone |
Antibodies |
Omalizumab | Binds IgE antibodies on mast cells; reduces reaction to inhaled antigen | Prophylaxis of severe, refractory asthma not responsive to all other drugs | Parenteral • administered as several courses of injections | Extremely expensive • long-term toxicity not yet well documented |