Which drug class is not given to a heart patient with asthma due to risk of bronchospasm?

Which drug class is not given to a heart patient with asthma due to risk of bronchospasm?

• A. Calcium channel blockers
• B. ACE inhibitors
• C. Beta blockers
• D. Diuretics

Answer: (C)

Blocking beta receptors in the lungs can prevent the bronchodilation that keeps airways open. In asthma, where the airways are already hyperreactive, drugs that block beta-2 receptors cause bronchoconstriction, worsening symptoms. That risk is why beta blockers are avoided in heart patients who have asthma. If a beta blocker is ever considered, a cardioselective agent that mainly blocks beta-1 receptors is sometimes used with caution, but many clinicians avoid them altogether because the potential for triggering bronchospasm remains, especially at higher doses or in more severe asthma. Other common heart medications don’t carry this risk. Calcium channel blockers act mainly on vascular smooth muscle and don’t directly cause airway constriction. ACE inhibitors don’t typically provoke bronchospasm (though they can cause cough for other reasons). Diuretics have no direct effect on bronchial smooth muscle.

Blocking beta receptors in the lungs can prevent the bronchodilation that keeps airways open. In asthma, where the airways are already hyperreactive, drugs that block beta-2 receptors cause bronchoconstriction, worsening symptoms. That risk is why beta blockers are avoided in heart patients who have asthma. If a beta blocker is ever considered, a cardioselective agent that mainly blocks beta-1 receptors is sometimes used with caution, but many clinicians avoid them altogether because the potential for triggering bronchospasm remains, especially at higher doses or in more severe asthma.

Other common heart medications don’t carry this risk. Calcium channel blockers act mainly on vascular smooth muscle and don’t directly cause airway constriction. ACE inhibitors don’t typically provoke bronchospasm (though they can cause cough for other reasons). Diuretics have no direct effect on bronchial smooth muscle.