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Adverse reactions with beta-adrenoceptor blocking drugs. An update
1Pontefract General Infirmary, West Yorkshire, England.
Drug Safety
|October 1, 1993
Summary
Beta-blockers can cause adverse reactions like bronchospasm, primarily due to beta 2-adrenoceptor blockade. Newer beta-blockers with beta 2-agonist activity may reduce risks, but caution is advised for patients with asthma or peripheral vascular disease.
Area of Science:
- Pharmacology
- Cardiology
- Pulmonology
Background:
- Beta-adrenoceptor blocking drugs are widely prescribed.
- Adverse reactions, including bronchospasm and peripheral ischemia, are often linked to beta 2-adrenoceptor blockade.
Purpose of the Study:
- To review the safety and efficacy of beta-blockers in patients with specific comorbidities.
- To discuss the implications of beta 2-selectivity and partial beta 2-agonist activity in newer beta-blockers.
Main Methods:
- Review of existing literature on beta-blocker pharmacology and clinical outcomes.
- Analysis of adverse event profiles associated with different classes of beta-blockers.
Main Results:
- Newer beta-blockers with enhanced beta 1-selectivity and partial beta 2-agonist activity generally show improved safety profiles for airways and vascular resistance.
- Despite improvements, no beta-blocker is entirely safe for asthmatic patients; alternatives like calcium antagonists, alpha-adrenoceptor antagonists, and ACE inhibitors exist.
- Beta-blockers with beta 2-agonist activity are preferred in patients with airways disease and ischemic heart disease, though bronchospasm risk and impaired bronchodilator response remain concerns.
- In peripheral vascular disease, beta-blockers with beta 2-agonist activity are less likely to exacerbate ischemia and may reduce peripheral coldness.
- Potential central nervous system effects, such as memory and concentration impairment, are noted but difficult to quantify.
- Rare, unpredictable adverse reactions include skin reactions, alopecia, and arthropathy.
Conclusions:
- While newer beta-blockers offer improved safety, careful patient selection and monitoring are crucial.
- Alternative antihypertensives are available for hypertensive patients with airways disease.
- In ischemic heart disease, beta-blockers with beta 2-agonist activity are beneficial but require vigilance for respiratory side effects.
- Beta-blockers with beta 2-agonist activity may be advantageous in peripheral vascular disease.
- The risk-benefit profile of beta-blockers must be individualized, considering potential adverse effects.
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