From the Guidelines
The correct answer is C. Tiotropium. Tiotropium is a long-acting muscarinic antagonist (LAMA) used primarily in the treatment of chronic obstructive pulmonary disease (COPD) and sometimes asthma. It works by blocking muscarinic receptors in the airways, which prevents acetylcholine from causing bronchoconstriction, thereby improving airflow. Tiotropium has a duration of action of approximately 24 hours, allowing for once-daily dosing. This distinguishes it from ipratropium (option B), which is a short-acting muscarinic antagonist (SAMA) that requires dosing multiple times per day. Albuterol (option A) and salmeterol (option D) are beta-2 agonists (short-acting and long-acting, respectively), not muscarinic antagonists. Montelukast (option E) belongs to an entirely different class of medications called leukotriene receptor antagonists, which work through a different mechanism to reduce airway inflammation. According to the study by Chong et al 1, tiotropium was associated with a lower rate of exacerbations compared with long-acting β-agonists, with an OR of 0.86 (95% CI, 0.79-0.93). Additionally, a systematic review compared tiotropium and ipratropium in the treatment of stable COPD, and tiotropium was superior to ipratropium in exacerbation prevention (OR, 0.71; 95% CI, 0.52-0.95) 1. The Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Lung Disease 2017 report also supports the use of LAMAs, such as tiotropium, in the treatment of COPD, as they have a greater effect on exacerbation reduction compared with LABAs (long-acting β-agonists) 1. Therefore, tiotropium is the correct answer, as it is a long-acting muscarinic antagonist (LAMA) that is effective in reducing exacerbations and improving lung function in patients with COPD.
From the FDA Drug Label
Tiotropium is a long-acting, muscarinic antagonist which is often referred to as an anticholinergic. The answer is: C. Tiotropium 2
From the Research
Long-Acting Muscarinic Antagonist (LAMA) Classification
- The correct answer is C. Tiotropium, as it is classified as a long-acting muscarinic antagonist (LAMA) 3, 4, 5, 6, 7.
Characteristics of Tiotropium
- Tiotropium bromide is a long-acting, once-daily inhaled anticholinergic approved for the treatment of chronic obstructive pulmonary disease (COPD) 4.
- Tiotropium is associated with increased lung function, health-related quality of life and exercise tolerance, and reduced dyspnea and acute exacerbations of COPD 4.
- Tiotropium is safe and well-tolerated, with few side effects 4.
Comparison with Other Medications
- Aclidinium bromide is also a long-acting muscarinic antagonist (LAMA) indicated for maintenance bronchodilator treatment of COPD, and has comparable efficacy to tiotropium 5.
- Glycopyrronium is another LAMA that has been compared to tiotropium in clinical studies, with similar results 5.
- Tiotropium has been combined with olodaterol, a long-acting β2-agonist (LABA), to reduce the risk of exacerbations in patients with COPD 7.