Certified Medical Assistant (CMA AAMA)PharmacologyHard
A medical assistant is educating a patient about a new prescription for metoprolol. The patient has a history of asthma. The medical assistant should inform the patient about which of the following potential adverse effects related to her asthma?
- ABronchoconstriction
- BWeight gain
- CIncreased blood sugar
- DPeripheral edema
Show answer & explanationAnswer & explanation
Correct answer: A. Bronchoconstriction
Metoprolol is a beta-blocker. While selective beta-1 blockers are generally safer for patients with asthma than non-selective ones, they can still cause bronchoconstriction by blocking beta-2 receptors in the lungs, especially at higher doses or in susceptible individuals. This can exacerbate asthma symptoms.
Why the other options are wrong
- B. Weight gain is not a primary or common adverse effect of metoprolol directly related to asthma.
- C. Increased blood sugar is a potential side effect of some beta-blockers, but less directly related to asthma exacerbation.
- D. Peripheral edema can be a side effect of some cardiovascular medications, but not a direct concern for asthma with metoprolol.
Beta-Blockers and Asthma
Beta-blockers, especially non-selective ones, can cause bronchoconstriction by blocking beta-2 adrenergic receptors in the lungs, leading to exacerbation of asthma symptoms. Even cardioselective beta-1 blockers can have this effect at higher doses or in sensitive patients.
- Beta-blockers block beta-adrenergic receptors.
- Beta-2 receptors in lungs cause bronchodilation when stimulated.
- Blocking beta-2 receptors can lead to bronchoconstriction.
- Use with extreme caution, if at all, in patients with asthma/COPD.
Memory trick: Beta-Blockers Block Breathing for Bronchial Patients.