Which medication should be avoided in a patient with asthma?

Which medication should be avoided in a patient with asthma?

• A. Propranolol
• B. Albuterol
• C. Theophylline
• D. Montelukast

Answer: (A)

The key idea is that blocking beta-2 receptors in the lungs can trigger bronchoconstriction, which is dangerous for someone with asthma. Propranolol is a nonselective beta-blocker, so it blocks both beta-1 receptors in the heart and beta-2 receptors in bronchial smooth muscle. By inhibiting beta-2 in the airways, it can cause or worsen bronchospasm, making asthma symptoms harder to control. That safety concern is why propranolol should be avoided in asthma. Other options don’t have this specific risk. Albuterol stimulates beta-2 receptors to relax airway smooth muscle and relieve wheezing. Theophylline, though less commonly used today, is a bronchodilator with a narrow therapeutic window and careful monitoring rather than a direct contraindication for asthma. Montelukast helps by blocking leukotriene-mediated inflammation.

The key idea is that blocking beta-2 receptors in the lungs can trigger bronchoconstriction, which is dangerous for someone with asthma. Propranolol is a nonselective beta-blocker, so it blocks both beta-1 receptors in the heart and beta-2 receptors in bronchial smooth muscle. By inhibiting beta-2 in the airways, it can cause or worsen bronchospasm, making asthma symptoms harder to control. That safety concern is why propranolol should be avoided in asthma.

Other options don’t have this specific risk. Albuterol stimulates beta-2 receptors to relax airway smooth muscle and relieve wheezing. Theophylline, though less commonly used today, is a bronchodilator with a narrow therapeutic window and careful monitoring rather than a direct contraindication for asthma. Montelukast helps by blocking leukotriene-mediated inflammation.