From the Research
Metoprolol does not typically cause cough as a side effect, unlike ACE inhibitors which are well-known for causing a dry, persistent cough. If a patient on metoprolol develops a cough, it's more likely due to another cause or medication. Metoprolol, a beta-blocker, can actually worsen asthma symptoms in some patients because it blocks beta-2 receptors in the lungs, potentially causing bronchoconstriction. This can manifest as wheezing, shortness of breath, or cough, particularly in patients with pre-existing asthma or COPD. For this reason, cardioselective beta-blockers like metoprolol are used with caution in asthmatic patients, and non-selective beta-blockers are generally avoided altogether. If a patient with asthma on metoprolol develops a new cough, it may represent worsening of their underlying respiratory condition rather than a direct medication side effect. Close monitoring is essential when initiating beta-blockers in patients with respiratory conditions, and any new or worsening respiratory symptoms should prompt medical evaluation, as suggested by the study on beta-blockers in asthma 1. The most recent and highest quality study on the topic of asthma treatment, which may be relevant to metoprolol-induced cough, is the 2021 Cochrane review on combination fixed-dose beta agonist and steroid inhaler as required for adults or children with mild asthma 2. However, this study does not directly address metoprolol-induced cough, but rather focuses on the treatment of mild asthma. Other studies, such as the 2023 systematic review and network meta-analysis on angiotensin-converting enzyme inhibitor induced cough, provide more information on cough as a side effect of other medications, but not metoprolol specifically 3. In summary, metoprolol is not typically associated with cough as a side effect, but it can worsen asthma symptoms, and close monitoring is necessary when using beta-blockers in patients with respiratory conditions.
Some key points to consider:
- Metoprolol is a cardioselective beta-blocker that can worsen asthma symptoms in some patients.
- Cough is not a typical side effect of metoprolol, but rather a potential symptom of worsening asthma or other respiratory conditions.
- Close monitoring is essential when initiating beta-blockers in patients with respiratory conditions.
- The treatment of mild asthma may involve combination fixed-dose beta agonist and steroid inhaler as required, as suggested by the 2021 Cochrane review 2.
- Other medications, such as ACE inhibitors, are more commonly associated with cough as a side effect, as shown in the 2023 systematic review and network meta-analysis 3.