This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
Bronchodilator in COPD 
Select and explain. 
A. Anticholinergics, B. Antiadrenergic, C. Cholinergic, D. Alfa agonists
A: Anticholinergics
Answer: A: Anticholinergics 
Explanation: Ans. is 'a' i.e., Anticholinergics Anticholinergic bronchodilators Anticholinergic acts on receptors located mainly in the larger central airways (Contrast sympathomimetics whose primary site of action is peripheral bronchioles). Parasympathetic tone is the major reversible factor in COPD. Anticholinergics are more effective than sympathomimetics. Ipratropium and tiotropium are anticholinergic bronchodilators. Tiotropium is longer acting than ipratropium. Inhaled ipratropium / tiotropium are bronchodilators of choice in COPD.