From the Guidelines
Beta blockers are contraindicated in asthmatic patients because they can trigger or worsen bronchospasm, potentially causing severe asthma attacks, as they block beta-adrenergic receptors, including beta-2 receptors in the lungs that normally help keep airways open when stimulated 1.
Key Considerations
- Non-selective beta blockers like propranolol, nadolol, and timolol pose the highest risk because they block both beta-1 and beta-2 receptors.
- Cardioselective beta blockers (such as metoprolol, atenolol, and bisoprolol) primarily target beta-1 receptors in the heart and may be used with extreme caution in some asthmatics when absolutely necessary, but they still carry some risk, especially at higher doses when selectivity diminishes.
- The mechanism involved in β-blocker–induced asthma is not completely understood, but antagonism of the β-adrenoreceptor, even with β-selective medications, should be avoided for patients with asthma 1.
Recommendations
- If a patient with asthma absolutely requires beta blocker therapy, it should be initiated at the lowest possible dose of a cardioselective agent with close monitoring for respiratory symptoms, and only after careful risk-benefit assessment by a physician.
- Beta blockers without intrinsic sympathomimetic activity should be used, especially beta-1 blockers such as sustained-release metoprolol succinate, bisoprolol, or carvedilol, a beta-1 and alpha-1 blocker, but with caution in patients with asthma 1.
Important Notes
- Asthma can also be exacerbated by certain drugs, such as nonsteroidal anti-inflammatory drugs and β-blockers, and aspirin-sensitive asthma is frequently associated with a genetic sequence variation and is relatively common in Eastern Europe and Japan 1.
- Beta blockers should be used prudently with ACE inhibitors or angiotensin-receptor blockers (ARBs) in patients with heart failure, and renin-angiotensin-aldosterone system blocking agents should be cautiously added in patients with decompensated heart failure 1.
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
Beta blockers are contraindicated in asthmatic patients because they may provoke a bronchial asthmatic attack by blocking bronchodilation produced by endogenous and exogenous catecholamine stimulation of beta-receptors 2. Key points include:
- Bronchospastic lung disease: Patients with this condition should not receive beta-blockers.
- Blocking bronchodilation: Beta blockers may block the bronchodilation produced by catecholamine stimulation of beta-receptors, leading to a bronchial asthmatic attack.
From the Research
Beta Blockers and Asthma
- Beta blockers are contraindicated in asthmatic patients because they can cause severe and sometimes fatal bronchoconstriction by blocking airway β2-receptors 3.
- Non-selective β-blockers should not be prescribed for the management of comorbidities in patients with asthma, as the risk of asthma worsening outweighs any potential benefits 4.
- Cardioselective β1-blockers may be safer than non-selective β-blockers, but they remain relatively contraindicated and under-prescribed in asthmatic patients 3, 4.
Risks and Benefits
- The benefits of cardioselective beta-blocker therapy outweigh the risks in patients with nonsevere asthma and a history of heart failure or myocardial infarction 5.
- Selective β1-blockers have a higher asthma risk signal compared to non-selective β-blockers, according to data from the Food and Drug Administration's Adverse Event Reporting System (FAERS) 6.
- Dual α- and β-blockers, hydrophilic, and lipophilic β-blockers pose lower asthma risks, while selective β1-blockers have higher risks regardless of intrinsic sympathomimetic activity 6.
Clinical Implications
- Clinicians should exercise caution when prescribing β-blockers to asthmatic patients or those predisposed to asthma, and consider alternative treatments when possible 4, 6.
- The risk stratification of different β-blocker classes can inform clinical decisions and patient management, with certain drugs like esmolol, metoprolol, nebivolol, and nadolol potentially being safer for asthmatic patients 6.