What are the contraindications for beta blockers (beta-adrenergic blocking agents)?

From the Guidelines

Beta blockers are contraindicated in patients with severe bradycardia, high-degree heart block, cardiogenic shock, decompensated heart failure, and those with risk factors for shock, as well as in patients with marked first-degree AV block, any form of second- or third-degree AV block in the absence of a functioning implanted pacemaker, a history of asthma, severe LV dysfunction or HF, or at high risk for shock. The contraindications for beta blockers can be categorized into absolute and relative contraindications. Absolute contraindications include severe bradycardia (heart rate below 50 beats per minute), high-degree heart block (second or third degree), cardiogenic shock, and decompensated heart failure 1. Relative contraindications where caution is needed include asthma and COPD due to risk of bronchospasm (especially with non-selective agents like propranolol), peripheral vascular disease, diabetes (as they can mask hypoglycemic symptoms), depression, and myasthenia gravis. Some key points to consider when prescribing beta blockers include:

• Starting with low doses and titrating slowly, especially in elderly patients or those with hepatic impairment
• Considering cardioselective agents (like metoprolol or bisoprolol) in patients with contraindications, which have less effect on bronchial smooth muscle and may be better tolerated in respiratory conditions
• Avoiding certain beta blockers in specific conditions, such as sotalol in patients with QT prolongation or significant renal impairment
• Being cautious when initiating beta blockers in patients who have required inotropes during hospitalization The most recent and highest quality study, published in 2022, provides guidance on the management of heart failure and recommends that beta blockers should not be withheld for mild or transient reductions in blood pressure or mild deteriorations in renal function 1. True contraindications are rare, such as advanced degree atrioventricular block for beta blockers in the absence of pacemakers, cardiogenic shock that may preclude use of certain medications until resolution of shock state, or angioedema for ACEi or ARNi. In patients with heart failure, beta blockers have been shown to reduce mortality and hospitalizations, and should be continued in patients with stable heart failure, but may need to be withheld or reduced in patients with marked volume overload or marginal low cardiac output 1. Overall, the use of beta blockers requires careful consideration of the patient's individual condition and medical history, and should be guided by the most recent and highest quality evidence.

From the FDA Drug Label

CONTRAINDICATIONS Hypersensitivity to metoprolol and related derivatives, or to any of the excipients; hypersensitivity to other beta-blockers (cross sensitivity between beta-blockers can occur). Myocardial Infarction Metoprolol is contraindicated in patients with a heart rate < 45 beats/min; second- and third-degree heart block; significant first-degree heart block (P-R interval ≥ 0.24 sec); systolic blood pressure < 100 mmHg; or moderate-to-severe cardiac failure WARNINGS ... Exacerbation of Bronchospastic Disease Patients with bronchospastic disease, should, in general, not receive beta-blockers, including metoprolol. The contraindications for beta blockers include:

• Hypersensitivity to beta-blockers or their excipients
• Heart rate < 45 beats/min
• Second- and third-degree heart block
• Significant first-degree heart block (P-R interval ≥ 0.24 sec)
• Systolic blood pressure < 100 mmHg
• Moderate-to-severe cardiac failure
• Bronchospastic disease (in general, although metoprolol may be used in some cases with caution) 2 2

From the Research

Beta Blocker Contraindications

• Absolute contraindications for beta blockers are rare, with only 3-5% of patients being intolerant due to hypotension or bradycardia 3
• Traditional contraindications to beta-blockers include peripheral vascular diseases, diabetes mellitus, chronic obstructive pulmonary disease (COPD), and asthma, but recent data suggest that these rules are not completely justified 4
• Beta-blockers should be avoided in patients with:
  • Vasospastic disorders, rest pain with severe peripheral vascular disease, or nonhealing lesions 4
  • History of asthma 4
  • Moderate to severe COPD, i.e., with FEV1 reduction < 50% of the predicted value 4
  • Chronic bronchodilator treatment 4
  • Chronic airflow limitation with evidence of > or = 20% reversibility in airway obstruction in response to inhaled salbutamol 4
• Beta-blockers are not contraindicated in:
  • Patients with mild to moderate peripheral vascular disease, but careful surveillance for any changes in symptoms related to intermittent claudication should be achieved 4
  • Patients with diabetes mellitus, but some caution should be addressed when signs of autonomic disease are present or in patients with difficult glycemic control 4
  • Patients with COPD, as they may benefit from beta-blockers due to their high cardiovascular risk, but monitoring of lung function during initiation is important 3
• Contraindications differ widely among beta blockers and should be cited for an individual drug, not for the entire class 5
• Some beta blockers, such as propranolol and carvedilol, are contraindicated in chronic obstructive lung disease, while others, such as nebivolol and bisoprolol, are not 5