Can propranolol (a non-selective beta-blocker) exacerbate respiratory symptoms, particularly in patients with asthma?

From the Guidelines

Propranolol can worsen breathing, especially in people with asthma, due to its non-selective beta-blocking effects on beta-2 receptors in the lungs, which can cause bronchoconstriction and trigger or worsen bronchospasm. According to the 2016 ESC guidelines for the diagnosis and treatment of acute and chronic heart failure 1, beta-blockers are only relatively contraindicated in asthma, but not in COPD, although a more selective β1-adrenoceptor antagonist is preferred. The contraindication to beta-blockers in asthma is based on small case series published in the 1980s and late 1990s with very high initial dosages in young patients with severe asthma. However, starting with low doses of cardioselective beta-blockers combined with close monitoring for signs of airway obstruction may allow the use of profoundly effective beta-blockers in patients with heart failure, especially in older people where true severe asthma is uncommon.

Some key points to consider when prescribing propranolol to patients with asthma or COPD include:

• Starting with low doses of cardioselective beta-blockers and monitoring for signs of airway obstruction
• Using cardioselective beta-blockers (like metoprolol or atenolol) as safer alternatives to propranolol
• Informing healthcare providers about any history of asthma or breathing problems before taking propranolol
• Considering the risks and benefits of using beta-blockers in patients with asthma or COPD, and using them under close medical supervision by a specialist.

It's also important to note that the 2011 ACCF/AHA focused update incorporated into the ACC/AHA 2007 guidelines for the management of patients with unstable angina/non-ST-elevation myocardial infarction 1 recommends that patients with a history of asthma should not receive beta blockers on an acute basis, and that beta blockers should be given very cautiously to patients with significant chronic obstructive pulmonary disease.

From the FDA Drug Label

CONTRAINDICATIONS Propranolol is contraindicated in 1) cardiogenic shock; 2) sinus bradycardia and greater than first-degree block; 3) bronchial asthma; and 4) in patients with known hypersensitivity to propranolol hydrochloride. Nonallergic Bronchospasm (e.g., Chronic Bronchitis, Emphysema): In general, patients with bronchospastic lung disease should not receive beta-blockers. Propranolol should be administered with caution in this setting since it may provoke a bronchial asthmatic attack by blocking bronchodilation produced by endogenous and exogenous catecholamine stimulation of beta-receptors

Propranolol can worsen breathing, especially in asthmatic patients. The drug label explicitly states that propranolol is contraindicated in patients with bronchial asthma and that it may provoke a bronchial asthmatic attack in patients with bronchospastic lung disease 2, 2. Key points:

• Propranolol is contraindicated in bronchial asthma
• May provoke a bronchial asthmatic attack in patients with bronchospastic lung disease
• Should be administered with caution in patients with bronchospastic lung disease

From the Research

Propranolol and Asthma

• Propranolol, a non-selective beta-blocker, can worsen breathing in asthmatic patients by inducing severe bronchoconstriction, even in those with mild asthma 3, 4, 5.
• The severity of bronchoconstrictor response to propranolol is not predictable and can occur at low doses, making it a significant concern for asthmatic patients 3.
• Studies have shown that propranolol can cause a significant decrease in lung function, including forced expiratory volume (FEV1) and peak expiratory flow rate (PEFR), in asthmatic patients 4, 5.

Comparison with Other Beta-Blockers

• Non-selective beta-blockers like propranolol are more likely to precipitate bronchospasms in patients with asthma compared to selective beta-blockers 6.
• Selective beta-blockers, such as cardioselective β1-blockers, may be safer for asthmatic patients, but their use should still be approached with caution 6, 7.
• The risk of bronchoconstriction with propranolol is higher compared to other beta-blockers, such as pindolol, which may have a more limited effect on large airways but can still cause significant bronchoconstriction in small airways 5.

Clinical Implications

• Asthmatic patients should avoid using propranolol and other non-selective beta-blockers due to the risk of severe bronchoconstriction 3, 4, 5.
• Alternative therapies, such as calcium antagonists, ACE inhibitors, and diuretics, should be considered for the management of hypertension and ischemic heart disease in asthmatic patients 3.
• The use of beta-blockers in asthma should be based on a risk assessment on an individual patient basis, taking into account the potential benefits and risks of treatment 6.